Such a sudden transition from the figure of the flock to that of a banquet is characteristic of Hebrew poetry.
Preparest — i.e., spreadest or furnishest, the usual phrase (Proverbs 9:2; Isaiah 21:5). (For the same figure of the hospitable host applied to God, see Job 36:16; Isaiah 25:6; and the well-known parables in the New Testament.)
In the presence of mine enemies. — We must imagine the banquet spread on some secure mountain height, in sight of the baffled foe, who look on in harmless spite.
My cup runneth over. — Literally, My cup is abundant drink. Cup, in the sense of portion, has already occurred (Psalms 11:6; Psalms 16:5). The LXX. has, “Thine intoxicating cup, how excellent it is;” Vulg. the same, but with “my” instead of “thy.”