The woman's love is intense, and his love is overwhelming.
If the Song is a collection of poems, the couple may be married. Their lovemaking is so exhausting that she feels faint and asks for raisin cakes and apples. In the ancient Near East, people considered these foods to be aphrodisiacs.
sustain me: She now relies on him to revive her with fruit from the earlier image—he is the apple tree, so he can provide apples to renew her strength.
His left hand is under my head: He tenderly supports her with his embrace as they lie together (see also Song of Solomon 8:3).