The portion. — There is allusion here to the Levitical portion (Numbers 18:20): “I am thy portion and thine inheritance.” The poet, whom we must imagine exiled from his actual inheritance in Canaan, consoles, and more than consoles himself, with the sublime thought that this “better part” could not be taken away from him. Perowne quotes Savonarola’s fine saying, “What must not he possess who possesses the possessor of all!” and St. Paul’s, “All things are yours; for ye are Christ’s, and Christ is God’s;” which rather recalls Deuteronomy 32:9, where the correlative truth to Numbers 18:20 occurs.
For the figure of the cup, see Psalms 11:6. It had already become a synonym for “condition in life.”
Thou maintainest. — The Hebrew word is peculiar, and causes grammatical difficulties; but the sense is clear. God does not only dispose (cast) the lot of the man in covenant relation to Him — He does that even for unbelievers — but holds it fast in His hand. (See this use of the verb, Amos 1:5; Amos 1:8; Proverbs 5:5.) At the same time Hitzig’s conjecture (tômîd for tômîkh), is very plausible, “Thou art ever my lot.”