Mentioned after the ascension of the Lord, in the upper room:
Acts 1:13 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.
Goes to Temple and heals a man:
Acts 3:1-4 Now Peter and John went up together into the temple at the hour of prayer, being the ninth hour. And a certain man lame from his mother’s womb was carried, whom they laid daily at the gate of the temple which is called Beautiful, to ask alms of them that entered into the temple; Who seeing Peter and John about to go into the temple asked an alms. And Peter, fastening his eyes upon him with John, said, Look on us.
Responds to all who were amazed:
Acts 3:11 And as the lame man which was healed held Peter and John, all the people ran together unto them in the porch that is called Solomon’s, greatly wondering.
Questioned at a meeting in Jerusalem:
Acts 4:6 And Annas the high priest, and Caiaphas, and John, and Alexander, and as many as were of the kindred of the high priest, were gathered together at Jerusalem.
Ministered with Peter:
Acts 4:13 Now when they saw the boldness of Peter and John, and perceived that they were unlearned and ignorant men, they marvelled; and they took knowledge of them, that they had been with Jesus.
Answered the Jewish leaders:
Acts 4:19 But Peter and John answered and said unto them, Whether it be right in the sight of God to hearken unto you more than unto God, judge ye.
Peter and John sent to Samaria:
Acts 8:14 Now when the apostles which were at Jerusalem heard that Samaria had received the word of God, they sent unto them Peter and John: