I remember precisely where I was the first time I heard a John Piper sermon. I was a sophomore in college, living in this small efficiency apartment. My senior pastor had mentioned the name John Piper several times, and told me once that I could listen to him on the radio. My interest in theology was just beginning to blossom and so I tuned in. That first sermon had as its primary text Psalm 16:11 and I remember thinking, “How have I never heard this passage before!” It was this text that turned me on to the entire world of Desiring God.
The phrase Desiring God refers not simply to the ministry of John Piper and Bethlehem Baptist Church in Minneapolis. In my case it is a reference to Piper’s Christian Hedonism, best captured by that famous phrase: God is most glorified in us when we are most satisfied in Him. The idea is that glorifying God brings us great joy, and so we ought to pursue it with fervent passion. His glory and our joy are not incompatible, or mutually exclusive. I might not have said it, but certainly for many years I had believed that either I can have fun and enjoy myself or I have to glorify God. Piper, and particularly that first sermon blew my mind.
Psalm 16:11 is a simple verse, packed with wonder. It reads:
You make known to me the path of life; in your presence there is fullness of joy; at your right hand are pleasures forevermore.
Piper expounded, in that simple sermon, the textual connection between the presence of God and pleasure. Service to God was not about duty, it was about delight. The phrase of “fullness joy” was particularly compelling too. Joy has levels, but the fullness of it is found only in the presence of God.
As I listened to that sermon and began to study this passage for myself I suddenly saw a whole world of joy open before me. I saw texts across the Scriptures that directed me to enjoy God, to delight in Him, to find pleasure in Him. These same words are picked up again in Acts 2:28. A multitude of Psalms echo this idea too. Some speak of God making people joyful (Ps. 21:6), others peak of finding delight in God’s presence (Ps. 37:4; Prov. 8:30). Even Jesus invites his servants into his joy (Matt. 25:23). This was a theme that I had never before really explored. My youth had been one of stressing duty to God, service, obedience, submission. All, of course, important themes, but there had been a real lack of emphasis on joy. Here was a passage of Scripture that was telling me I could have fun and worship God and that in fact the latter was key to the former. It was joy and pleasure to be in His presence. Psalm 16:11 was shocking in its description of joy.
I began to devour books by Piper that discussed these same textual themes. I read The Dangerous Duty of Delight, Desiring God, God’s Passion for His Glory, Future Grace, A Hunger for God, and God is the Gospel. I was, from Piper, turned on to other authors saying similar things: Jonathan Edwards, C.S. Lewis, and Sam Storms. I was enraptured by this idea of glorifying God by enjoying God. I was fascinated by the very possibility of enjoying God. I had loved God, but now opening before me was the possibility that I might not just love Him, but enjoy Him. That was captivating and overwhelming. If I haven’t read anything by Piper in maybe eight years now, I will never forget those early impressions he made upon me, and most significantly from preaching this one passage: Psalm 16:11.
I have memorized this verse and used it as a reminder of the joy with which I can and should seek God. In many ways God used this verse to do precisely what it says He will do. The text says “You have made known to me the path of life.” That is, the Psalmist is saying that God himself revealed the path of life and joy and pleasure to him. The text is, in part, a fulfillment of that truth, for through it God made known to me this path. God used this very verse to fulfill its content. He made known to me the path of life and joy and pleasure through Psalm 16:11 and I am forever grateful for it.
Pastor Dave Online 
Encouraging! Thank you!