v. 5-7 Thou has put gladness in my heart...
Trusting God is called into question. Pascal's Wager tested by Libertarians: But if God is not real, then we would have wasted our time devoting to a presumed God.
The answer is in v. 7. That in our trust and devotion, God put gladness in our hearts, that which is beyond worldly satisfaction. Devotion is not sacrifice for the worse, it is for the best. Thus, everything in our lives are enjoyed, how then, is it a waste?