Heidelberg Catechism · 1563

Q72. Does this outward washing with water itself wash away sins?

No, only the blood of Jesus Christ and the Holy Spirit cleanse us from all sins.
Answer · Heidelberg Catechism

Scripture proofs

  1. [1]
    Matthew 3:11

    I indeed baptize you with water unto repentance: but he that cometh after me is mightier than I, whose shoes I am not worthy to bear: he shall baptize you with the Holy Ghost, and with fire:

    1 Peter 3:21

    The like figure whereunto even baptism doth also now save us (not the putting away of the filth of the flesh, but the answer of a good conscience toward God,) by the resurrection of Jesus Christ:

    1 John 1:7

    But if we walk in the light, as he is in the light, we have fellowship one with another, and the blood of Jesus Christ his Son cleanseth us from all sin.

Proof texts as given in the original; verse text from the King James Version.