This is a true apostolic saying: What he elsewhere referred to as: “Baptised into Christ’s death and buried with Him in baptism,” he here describes as “planted together into the likeness of His death.” Thus he binds and knits together Christ’s death and resurrection and our baptism, in order that baptism should not be thought of as a mere sign, but that the power of both Christ’s death and resurrection are contained in it. And this is so in order that there should also follow in us both death and resurrection. For our sin is slain through His death, that is, taken away, in order that it may no longer live in us but die and be dead for ever.

Thus, that in baptism we are sunk under the water indicates that we too die in Christ, but that we emerge again means and imparts to us new life in Him, just as He did not remain in death but rose again. But such a life should not and cannot be a life in sin because sin has already been slain in us and we have died unto sin; but it must be a new life of righteousness and holiness. Thus we are no called “planted into Christ” and “made one with Him,” and, as it were, baked into one loaf, and we receive into ourselves both the power of His death and His resurrection, and also, the fruit or consequence of it is found in us, since we have been baptised in Him. (Martin Luther, 1535 sermon on Romans 6)