Charles Ellicott Commentary Romans 7:14

"For we know that the law is spiritual: but I am carnal, sold under sin." — Romans 7:14 (ASV)

For we know.—There is no need to argue the question. We Christians all know that the Law is spiritual. It is divinely given and inspired.

On the other hand, on the other hand, man, though capable of communion with God, is dominated by that part of his nature which is the direct opposite of divine, and is entirely earthly and sensual. This sensual part of his nature is the slave—and just as much the slave as if he had been sold in the auction mart—of Sin (Compare to 1 Kings 21:20; 1 Kings 21:25).

On verses 14-25:

Further and detailed proof of why, though the Law appealed to all that was best in man, he still could not obey it.