Charles Ellicott Commentary Psalms 18:50

"Great deliverance giveth he to his king, And showeth lovingkindness to his anointed, To David and to his seed, for evermore." — Psalms 18:50 (ASV)

This verse is by many treated as a late liturgical addition to the hymn. The change to the third person is certainly somewhat suggestive of this, but by no means conclusive.

The question of the relationship between the two copies of this hymn is far too complicated and difficult for discussion here. Each has been repeatedly claimed as the original. The best explanation of the variations is that the compositions were independent copies of some original, and that the psalm, like many others, was altered in preparation for choir use.