New Defender's Study Bible Notes
8:8 to retain the spirit. A man’s spirit has been given him by God, and its continued presence in the body is beyond man’s power to assure. Only Jesus, in His humanity, was able arbitrarily to dismiss His spirit when He was ready; no man could have taken it from Him until then (Luke 23:46; John 10:17,18).
8:11 not executed speedily. The apparent prosperity of the wicked has long been both a stumbling block to faith and an encouragement to evil doers. Yet Solomon knew that the sentence would indeed be fully executed eventually and that “it shall be well with them that fear God” (Ecclesiastes 8:12-13).
8:15 to be merry. If there were no God, and no eternity to spend in heaven or hell, then this philosophy of life “under the sun” would be as good as any other. Morality, social justice, and all supposed “good” values would be pointless. Why not “live it up” any way one can! Note I Corinthians 15:19,32. But Christ has conquered death, and thus vindicated all of God’s revelation. This life is not all there is, and it does make a difference!