The reading is from Acts of the Apostles 2:38-43

In those days, Peter said to the people, "Repent and be baptized every one of you in the name of Jesus Christ for the forgiveness of your sins; and you shall receive the gift of the Holy Spirit. For the promise is to you and to your children and to all that are far off, every one whom the Lord our God calls to him." And he testified with many other words and exhorted them, saying, "Save yourselves from this crooked generation." So those who received his word were baptized, and there were added that day about three thousand souls. And they devoted themselves to the apostles' teaching and fellowship, to the breaking of bread and the prayers. And fear came upon every soul; and many wonders and signs were done through the apostles.