Westminster Shorter Catechism
Question 88

Q: What are the outward means whereby Christ communicateth to us the benefits of redemption?
A: The outward and ordinary means whereby Christ communicateth to us the benefits of redemption are, his ordinances, especially the word, sacraments, and prayer; all of which are made effectual to the elect for salvation.

Matthew 28:19-20. Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost: teaching them to observe all things whatsoever I have commanded you: and, lo, I am with you alway, even unto the end of the world. Amen.
Acts 2:41-42, 46-47. Then they that gladly received his word were baptized: and the same day there were added unto them about three thousand souls. And they continued stedfastly in the apostles' doctrine and fellowship, and in breaking of bread, and in prayers. . . And they, continuing daily with one accord in the temple, and breaking bread from house to house, did eat their meat with gladness and singleness of heart, praising God, and having favour with all the people. And the Lord added to the church daily such as should be saved.

Westminster Project - Matthew Henry's Scripture Catechism based on the WSC.