They Were In One Accord, Acts 1-2.

for John truly baptized with water, but you shall be baptized with the Holy Spirit not many days from now.” And He said to them, “It is not for you to know times or seasons which the Father has put in His own authority. But you shall receive power when the Holy Spirit has come upon you; and you shall be witnesses to Me in Jerusalem, and in all Judea and Samaria, and to the end of the earth.” And when they had entered, they went up into the upper room where they were staying: Peter, James, John, and Andrew; Philip and Thomas; Bartholomew and Matthew; James the son of Alphaeus and Simon the Zealot; and Judas the son of James. These all continued with one accord in prayer and supplication, with the women and Mary the mother of Jesus, and with His brothers. “Men and brethren, this Scripture had to be fulfilled, which the Holy Spirit spoke before by the mouth of David concerning Judas, who became a guide to those who arrested Jesus; for he was numbered with us and obtained a part in this ministry.” When the Day of Pentecost had fully come, they were all with one accord in one place. And suddenly there came a sound from heaven, as of a rushing mighty wind, and it filled the whole house where they were sitting. Then there appeared to them divided tongues, as of fire, and one sat upon each of them. And they were all filled with the Holy Spirit and began to speak with other tongues, as the Spirit gave them utterance.
Acts 1:5,7-8,13-14,16-17,2:1-4 - NKJV