Having traced and studied the apostle Peter through the first four gospels, you will next take a look in the "book of Acts of the apostles" to learn more about Peter— the man with the keys to the kingdom.

The book of Acts begins with where the four gospels close, regarding the ministry, death, burial, and the resurrection of Jesus, the Christ.

From the narrative opening scriptures of the book of Acts, one can see that Jesus has already been risen from the grave, and has now appeared (many times) to His disciples for a time period of "forty days" before he will ascend to His father sending —the promise of His Father, YHWH —the anointing of the Holy Ghost.

Acts 1:1-5 (KJV)
The former treatise have I made, O Theophilus, of all that Jesus began both to do and teach, [2] Until the day in which he was taken up, after that he through the Holy Ghost had given commandments unto the apostles whom he had chosen: [3] To whom also he shewed himself alive after his passion by many infallible proofs, being seen of them forty days, and speaking of the things pertaining to the kingdom of God: [4] And, being assembled together with them, commanded them that they should not depart from Jerusalem, but wait for the promise of the Father, which, saith he, ye have heard of me. [5] For John truly baptized with water; but ye shall be baptized with the Holy Ghost not many days hence.

The very next line states something very crucial to understanding the setting, and the time period, and the state of the full understanding of his own twelve disciples regarding why Messiah had come, and was to come; the focal reason why Jesus was sent by God.

Christ's disciples asked a very direct question to Jesus.

Acts 1:6 (KJV)
When they therefore were come together, they asked of him, saying, Lord, wilt thou at this time restore again the kingdom to Israel?

Understanding what this (often over looked question) means, will help you to understand what Peter, no doubt, also understood and taught in his very first sermons to the children of Israel and those who assembled in Jerusalem from many other far nations.

The word "Israel" here, also denotes the twelve tribes of Israel.

The next lines give us the answer of Jesus to His disciples.

Acts 1:7-11 (KJV)
And he said unto them, It is not for you to know the times or the seasons, which the Father hath put in his own power. [8] But ye shall receive power, after that the Holy Ghost is come upon you: and ye shall be witnesses unto me both in Jerusalem, and in all Judaea, and in Samaria, and unto the uttermost part of the earth. [9] And when he had spoken these things, while they beheld, he was taken up; and a cloud received him out of their sight. [10] And while they looked stedfastly toward heaven as he went up, behold, two men stood by them in white apparel; [11] Which also said, Ye men of Galilee, why stand ye gazing up into heaven? this same Jesus, which is taken up from you into heaven, shall so come in like manner as ye have seen him go into heaven.

Also note what takes place after Jesus ascends in the clouds, the reaction of his disciples who are standing and staring up into the clouds.

Two men (or angels) give a rebuke to the disciples as if to say 'why are you so in awe staring into the clouds when there is much work to be done? For Christ shall return one day in a like manner as He ascended.'

"Why stand ye gazing up into heaven?"

The modern day church can certainly learn something from this lesson. Instead of waiting for Christ's return or "the rapture" there's much work to be done, so pray that the Lord sends workers into his harvest.

Peter and all the disciples are gathered to wait upon YHWH's promise at Jerusalem.

Acts 1:12-14 (KJV)
Then returned they unto Jerusalem from the mount called Olivet, which is from Jerusalem a sabbath day's journey. [13] And when they were come in, they went up into an upper room, where abode both Peter, and James, and John, and Andrew, Philip, and Thomas, Bartholomew, and Matthew, James the son of Alphaeus, and Simon Zelotes, and Judas the brother of James. [14] These all continued with one accord in prayer and supplication, with the women, and Mary the mother of Jesus, and with his brethren.

Peter's first sermon to his disciples uses scripture and takes up the task of fulfilling a need of the ministry, that is replacing the lost apostle, Judas of Iscariot.

Acts 1:15-26 (KJV)
And in those days Peter stood up in the midst of the disciples, and said, (the number of names together were about an hundred and twenty,) [16] Men and brethren, this scripture must needs have been fulfilled, which the Holy Ghost by the mouth of David spake before concerning Judas, which was guide to them that took Jesus. [17] For he was numbered with us, and had obtained part of this ministry. [18] Now this man purchased a field with the reward of iniquity; and falling headlong, he burst asunder in the midst, and all his bowels gushed out. [19] And it was known unto all the dwellers at Jerusalem; insomuch as that field is called in their proper tongue, Aceldama, that is to say, The field of blood. [20] For it is written in the book of Psalms, Let his habitation be desolate, and let no man dwell therein: and his bishoprick let another take. [21] Wherefore of these men which have companied with us all the time that the Lord Jesus went in and out among us, [22] Beginning from the baptism of John, unto that same day that he was taken up from us, must one be ordained to be a witness with us of his resurrection. [23] And they appointed two, Joseph called Barsabas, who was surnamed Justus, and Matthias. [24] And they prayed, and said, Thou, Lord, which knowest the hearts of all men, shew whether of these two thou hast chosen, [25] That he may take part of this ministry and apostleship, from which Judas by transgression fell, that he might go to his own place. [26] And they gave forth their lots; and the lot fell upon Matthias; and he was numbered with the eleven apostles.

It is important to God's plan to have exactly twelve disciples, not eleven, for as Christ taught His disciples, they would in time sit upon twelve thrones judging the twelve tribes of Israel.

The Next scripture we see the day of Pentecost arrives

Acts 2:1 (KJV)
And when the day of Pentecost was fully come, they were all with one accord in one place.

The day of Pentecost is the fiftieth day which followed the Passover week, or the day that ends seven counted sabbaths after the first fruit offering, which would have taken place on the day following last day of the feast of unleavened bread. 

Note that Jesus appeared forty days and then ascends and tells his disciples to tarry at Jerusalem. 

The day of Pentecost was also the very same day that Moses first received the ten commandments tablets from YHWH God on Mt Sinai.

Acts 2:2-4 (KJV)
And suddenly there came a sound from heaven as of a rushing mighty wind, and it filled all the house where they were sitting. [3] And there appeared unto them cloven tongues like as of fire, and it sat upon each of them. [4] And they were all filled with the Holy Ghost, and began to speak with other tongues, as the Spirit gave them utterance.

Its on the very same day that God's law was given to Moses —the first covenant with Israel, the Holy Spirit, the promise of Jesus' Father (YHWH), falls upon the twelve disciples at Jerusalem—the New Covenant God made with the children of Israel.

Note closely what happened this day.

Acts 2:4-13 (KJV)
And they were all filled with the Holy Ghost, and began to speak with other tongues, as the Spirit gave them utterance. [5] And there were dwelling at Jerusalem Jews, devout men, out of every nation under heaven. [6] Now when this was noised abroad, the multitude came together, and were confounded, because that every man heard them speak in his own language. [7] And they were all amazed and marvelled, saying one to another, Behold, are not all these which speak Galilaeans? [8] And how hear we every man in our own tongue, wherein we were born? [9] Parthians, and Medes, and Elamites, and the dwellers in Mesopotamia, and in Judaea, and Cappadocia, in Pontus, and Asia, [10] Phrygia, and Pamphylia, in Egypt, and in the parts of Libya about Cyrene, and strangers of Rome, Jews and proselytes, [11] Cretes and Arabians, we do hear them speak in our tongues the wonderful works of God. [12] And they were all amazed, and were in doubt, saying one to another, What meaneth this? [13] Others mocking said, These men are full of new wine.

The apostles were filled with Holy Ghost and then spoke in "tongues."

By the power of God, all those who came together hearing the noise each from diverse lands and each speaking different languages, all heard the apostles, "the Galileans," speaking in their own language.

Some then began to doubt in this miracle, accusing them of being drunken babblers. It's then that the apostle Peter speaks up in what is to be Peter's first public sermon of the Church age.

Note closely again, how Peter addresses the crowd.

Acts 2:14-36 (KJV)
But Peter, standing up with the eleven, lifted up his voice, and said unto them, Ye men of Judaea, and all ye that dwell at Jerusalem, be this known unto you, and hearken to my words: [15] For these are not drunken, as ye suppose, seeing it is but the third hour of the day. [16] But this is that which was spoken by the prophet Joel; [17] And it shall come to pass in the last days, saith God,I will pour out of my Spirit upon all flesh: and your sons and your daughters shall prophesy, and your young men shall see visions, and your old men shall dream dreams: [18] And on my servants and on my handmaidens I will pour out in those days of my Spirit; and they shall prophesy: [19] And I will shew wonders in heaven above, and signs in the earth beneath; blood, and fire, and vapour of smoke: [20] The sun shall be turned into darkness, and the moon into blood, before that great and notable day of the Lord come: [21] And it shall come to pass, that whosoever shall call on the name of the Lord shall be saved. [22] Ye men of Israel, hear these words; Jesus of Nazareth, a man approved of God among you by miracles and wonders and signs, which God did by him in the midst of you, as ye yourselves also know: [23] Him, being delivered by the determinate counsel and foreknowledge of God, ye have taken, and by wicked hands have crucified and slain: [24] Whom God hath raised up, having loosed the pains of death: because it was not possible that he should be holden of it. [25] For David speaketh concerning him, I foresaw the Lord always before my face, for he is on my right hand, that I should not be moved: [26] Therefore did my heart rejoice, and my tongue was glad; moreover also my flesh shall rest in hope: [27] Because thou wilt not leave my soul in hell, neither wilt thou suffer thine Holy One to see corruption. [28] Thou hast made known to me the ways of life; thou shalt make me full of joy with thy countenance. [29] Men and brethren, let me freely speak unto you of the patriarch David, that he is both dead and buried, and his sepulchre is with us unto this day. [30] Therefore being a prophet, and knowing that God had sworn with an oath to him, that of the fruit of his loins, according to the flesh, he would raise up Christ to sit on his throne; [31] He seeing this before spake of the resurrection of Christ, that his soul was not left in hell, neither his flesh did see corruption. [32] This Jesus hath God raised up, whereof we all are witnesses. [33] Therefore being by the right hand of God exalted, and having received of the Father the promise of the Holy Ghost, he hath shed forth this, which ye now see and hear. [34] For David is not ascended into the heavens: but he saith himself, The Lord said unto my Lord, Sit thou on my right hand, [35] Until I make thy foes thy footstool. [36] Therefore let all the house of Israel know assuredly, that God hath made that same Jesus, whom ye have crucified, both Lord and Christ.

Note that Peter in his first sermon addresses the crowd first to the Jews of the house of Judah, those living in Judea and mostly residing in Jerusalem. Later Peter addresses "ye men of Israel" then lastly he addresses "all the house of Israel."

It's important to note that the house Judah, was only two tribes (Judah and Benjamin) of the remaining visible remnant of Israel (all 12 tribes).

It's also important to note there once were ten tribes of the house of Israel who were not of the tribe of Judah, were not biblically ever refered to as "Jews,"(Judahites) but were instead lost and scattered of into the "gentile" lands of what later became known as regions of the: Parthians, Medes, Elamites, Mesopotamia, Judaea, Galacia, Pontus, Asia, Phrygia, and Pamphylia, Cyrene, Rome, Greecia, etc.

Amazingly here in Jerusalem, on the very important day the Holy Ghost descends, are people gathered from all of these regions and the apostles later will begin to preach, setting up churches exactly in these regions as the book of Acts witnesses.

Next notice the reaction of those hearing this sermon by Peter.

Acts 2:37 (KJV)
Now when they heard this, they were pricked in their heart, and said unto Peter and to the rest of the apostles, Men and brethren, what shall we do?

The Scripture states these men of Judah where pricked to their heart, their consciences, to believe.

It was on Peter, that Jesus stated he would build His church, giving Peter the keys to the kingdom of heaven.

Matthew 16:17-20 (KJV)
[17] And Jesus answered and said unto him, Blessed art thou, Simon Barjona: for flesh and blood hath not revealed it unto thee, but my Father which is in heaven. [18] And I say also unto thee, That thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it. [19] And I will give unto thee the keys of the kingdom of heaven: and whatsoever thou shalt bind on earth shall be bound in heaven: and whatsoever thou shalt loose on earth shall be loosed in heaven. [20] Then charged he his disciples that they should tell no man that he was Jesus the Christ.

The very next scripture is perhaps one or all of "the keys" to opening the doors to the kingdom of heaven.

Acts 2:38-39 (KJV)
Then Peter said unto them, Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost. [39] For the promise is unto you, and to your children, and to all that are afar off, even as many as the Lord our God shall call.

Peter said to them "REPENT" of their sins and "Be baptized." 
 
But why did Peter say one had to be baptized?

Peter clearly stated it was "for the remission of sins." Then Peter says in same breath "and ye shall receive the gift of the Holy Ghost."

So the process of baptism in water calling on the name of the Lord Jesus was a physical ordinance which resulted in a Spiritual gift— "and ye shall receive the gift of the Holy Ghost."

Peter further clarifies this saying "For the promise is unto you, and to your children, and to all that are afar off, even as many as the Lord our God shall call."

Here we have the very keys of the kingdom being used on the day of Pentecost by Peter, the rock, and foundation of Christ's Church.

Acts 2:40-47 (KJV)
And with many other words did he testify and exhort, saying, Save yourselves from this untoward generation.
[41] Then they that gladly received his word were baptized: and the same day there were added unto them about three thousand souls. [42] And they continued stedfastly in the apostles' doctrine and fellowship, and in breaking of bread, and in prayers. [43] And fear came upon every soul: and many wonders and signs were done by the apostles. [44] And all that believed were together, and had all things common; [45] And sold their possessions and goods, and parted them to all men, as every man had need. [46] And they, continuing daily with one accord in the temple, and breaking bread from house to house, did eat their meat with gladness and singleness of heart, [47] Praising God, and having favour with all the people. And the Lord added to the church daily such as should be saved.

It's clear that those who heard Peter's sermon and his command of what they should do, acted immediately.

"Then they that gladly received his word were baptized: and the same day there were added unto them about three thousand souls.  And they continued stedfastly in the apostles' doctrine and fellowship, and in breaking of bread, and in prayers"

Peter used his keys that Christ gave him and three thousand of fellow Judaites or Israelites were entered into the New Covenant relationship with Jesus the Christ.

Do You now Believe?

Do you know what you shall do?

Have you been washed in the Blood of the Lamb?

Have you repented of your sins before God?

What is preventing you from being Baptized?

This concludes Part 2 of the apostle Peter: the man with the keys to the kingdom of heaven.

The third part of this study will focus on what Peter did after begining the Church of Christ on earth.