"You will show me the way of life, granting me the joy of your presence and the pleasures of living with you forever." (‭Psalms‬ ‭16‬:‭11‬ NLT)
 
Peter quoted from Psalm 16:8-11—a psalm written by David. He explained that David was not writing about himself because David died and was buried (2:29). Instead, he was writing as a prophet (2:30) who spoke of the Messiah who would be resurrected. The emphasis here is that Jesus’ body was not left to rot in the grave but was, in fact, resurrected and glorified. (Tyndal Study Bible)
 
If you have time, read the whole Psalm. It's amazing. Summarized so well in the last verse.
 
David says that God will show him the way of life. And off course He will show us, granting us the joy of His presence and guidance.  The whole psalm speaks of God and how He looks out for us. We can rely on Him all the time.
 
The promise of heaven and eternal life - God won't ever leave or forsake us. How long is eternal? The answer is forever. How grateful we should be.
 
If we believe, He won't leave us to rot in hell. We will rise to Heaven.
 
Can you imagine?
 
"Lord, I pray thanks for You being there for me. Eternally. Amen"