Charles Ellicott Commentary John 1:17

"For the law was given through Moses; grace and truth came through Jesus Christ." — John 1:17 (ASV)

The word "for" connects this verse by way of explanation with what has gone before. The Old Testament thought of grace and truth has already been present in John 1:14. The fullness of these divine attributes has been beheld in the glory of the Word. The revelation of them, that is, the removing of the veil which hides what is knowable, has been made dependent on the use of what is already known.

But this is the essence of Christianity as distinct from Judaism; of a spiritual religion developed from within, as distinct from a formal religion imposed from without; of a religion of principles, and therefore true for all time and for all people, as distinct from a religion of works, based indeed on an eternal truth (the oneness and the righteousness of God) but still specially designed for a chosen people and for a period of preparation.

The law was given (from without) by the human agency of Moses. The true grace and truth came into being by means of Jesus Christ. Therefore, we receive grace for grace, since in Him there is an ever-constant fullness of grace, and for the one who uses the grace so given, there is an ever-constant realization of deeper truth.

Note that here, when His divinity and humanity have both been dwelt upon, and in contrast to the historic Moses, the name Jesus Christ first appears. Is there, too, in this union of the human and divine names a reference to the union in Him of the faculty to receive and the truth to fulfill? St. Luke speaks of Him as increasing in wisdom and stature, and in favour (grace) with God and man (Luke 2:52; see Note there).