Holy Baptism
Q51. How can water do such great things?
Certainly not just water, but the word of God in and with the water does these things, along with the faith which trusts this word of God in the water. For without God's word the water is plain water and no Baptism. But with the word of God it is a Baptism, that is, a life-giving water, rich in grace, and a washing of the new birth in the Holy Spirit.
Scripture Proofs — King James Version
1
Titus 3:5–7
Ephesians 5:26
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:”
Read Luther’s expanded teaching
From the Large Catechism (1529)