Verses with the word join in the New Testament (3 verses):

Acts 5:13
And of the rest durst no man join himself to them: but the people magnified them.

Acts 8:29
Then the Spirit said unto Philip, Go near, and join thyself to this chariot.

Acts 9:26
And when Saul was come to Jerusalem, he assayed to join himself to the disciples: but they were all afraid of him, and believed not that he was a disciple.