Acts 2:41-43

So then, those who accepted his message were baptized; and on that day about 3,000 souls were added [to the body of believers]. They were continually and faithfully devoting themselves to the instruction of the apostles, and to fellowship, to eating meals together and to prayers. A sense of awe was felt by everyone, and many wonders and signs (attesting miracles) were taking place through the apostles.