"Let my prayer be set forth in Your sight as incense, and the lifting up of my hands an evening sacrifice" (Psalm 140:2). That this is wont to be understood of the Head Himself, every Christian acknowledges. For when the day was now sinking towards evening, the Lord upon the Cross "laid down His life to take it again," (John 10:17) did not lose it against His will. Still we too are figured there. For what of Him hung upon the tree, save what He took of us? And how can it be that the Father should leave and abandon His only begotten Son, especially when He is one God with Him? Yet, fixing our weakness upon the Cross, where, as the Apostle says, "our old man is crucified with Him," (Romans 6:6) He cried out in the voice of that our "old man," "Why have You forsaken Me?" That then is the "evening sacrifice," the Passion of the Lord, the Cross of the Lord, the offering of a salutary Victim, the whole burnt offering acceptable to God. That "evening sacrifice" produced, in His Resurrection, a morning offering. Prayer then, purely directed from a faithful heart, rises like incense from a hallowed altar. Nought is more delightful than the odour of the Lord: such odour let all have who believe.
Augustine, Exposition on Psalm 141. There's some interesting rhetorical virtuosity here: the play on 'lifting up of my hands', where it represents simultaneously both Christ's hanging on the cross and lifting up hands in Christian prayer, which is paralleled by the play on incense, which can be taken as incense in the strict sense, a symbol of prayer, or incense in the broader sense that includes the scent of a sacrifice, which is a symbol of Christ; all deliberately used to indicate that the faithful Christian at prayer is united with Christ on the Cross, and to suggest that therefore both are in preparation for Resurrection.