But my horn shalt thou exalt - The horn is a symbol of strength or power (see the notes at Psalms 18:2); and the meaning here is, that, while the wicked would be cut off, he would be prospered; that is, he had such confidence that he was the friend of God, that he believed God would honor him and exalt him. The psalmist here speaks of himself not so much with reference to his own particular case, but as the representative of the righteous. The idea is, that God will thus exalt “a righteous man.”
Like the horn of an unicorn - Supposed to be remarkable for the strength of its horn. On the animal here referred to, see the notes at Job 39:9; compare Psalms 22:21.
I shall be anointed with fresh oil - Oil pure and sweet; not old and rancid. That is, he would be made happy, cheerful, bright, and prosperous. Anointing with oil in the East was the symbol of all this, or was equivalent to what we mean by putting on festive apparel - holiday apparel. Compare the notes at Psalms 23:5.