"You will not abandon me to the realm of the dead, nor will you let your faithful one see decay." (Psalm 16:10)
Psalm 16 is one of the most theologically rich psalms in the entire Psalter, and St. Peter quotes it in his Pentecost sermon as the definitive prophecy of the Resurrection of Christ (Acts 2:25-28). David opens with complete dependence: Keep me safe, my God, for in you I take refuge. He then declares that his good does not extend beyond God: everything good he has comes from the Lord. His portion and his cup, his inheritance, the boundary lines of his life have fallen in pleasant places. He has the most beautiful inheritance of all: the Lord himself.
The middle of the psalm is a meditation on the presence of God as the source of all stability: I keep my eyes always on the Lord. With him at my right hand, I will not be shaken. Therefore my heart is glad and my tongue rejoices; my body also will rest secure. The gladness and the security are both rooted in the same thing: the presence of the Lord at his right hand. This is the posture that St. Ignatius of Loyola later called "finding God in all things": the constant attentiveness to the divine presence that transforms ordinary experience into an encounter with the sacred.
You will not abandon me to the realm of the dead, nor will you let your faithful one see decay. You make known to me the path of life; you will fill me with joy in your presence, with eternal pleasures at your right hand. Peter at Pentecost makes the argument explicit: David died, his tomb is still with us, so this psalm cannot ultimately be about David. It is the prophecy of the one of David's descendants who was raised before his body could see corruption. The resurrection of Jesus Christ is the fulfilment of Psalm 16, the vindication of the faithful one whom God did not abandon to death.
Brothers and sisters, the path of life that David prays to be shown is the path we walk in Christ. The joy in God's presence that he anticipates is the joy of the Beatific Vision that awaits the redeemed. Set the Lord always before you. With him at your right hand, you will not be shaken. And the body that rests in the grave will not see decay, because the one who fulfilled Psalm 16 will raise it on the last day.
Lord God, keep us safe in your refuge. Let the boundary lines of our lives fall in pleasant places. Make known to us the path of life. And at the last, do not abandon us to death, but fill us with joy in your presence, with eternal pleasures at your right hand. Through Christ our Lord. Amen.