The word here translated "a good man" is literally "a hero," "a valiant man." As John Bunyan put it: "Mr. Valiant-for-the-truth." God delights in his way. That's why he must prosper, even though he goes through many trials, as did Joseph (Gen. 39:2-6, 21-23).
Notice, this promise does not assure a good person that they will never fail, but that if they do, they will not be "utterly cast down." The Lord will take them by the hand and raise them again. We have a beautiful picture of this in Matthew 14:31. Peter was sinking beneath the angry waves, and Jesus stretched forth His hand to save him. Peter's short prayer may often be ours, "Lord, save me."
The writer remembers receiving two terrific blows--one from falling on the ice in learning to skate, the other from a senior minister who gave some very hard, but much needed, rebuke. Both were hard to endure, but were blessed in their outcome.
Stuart Hutchinson tells of his minister father, whose hobby was that of a vinedresser. Late in the winter he would cut the vines until it seemed that he would kill them, but when the next September came, the heavy clusters of grapes proved he was right in what he did. On the hill behind the house was a wild grapevine. One day Stuart said, "Father, why don't you trim that vine?"
"Oh," he replied, "it isn't worth it."
Sometimes when God sends disappointments and trials we think He doesn't love us; but remember, He is with us. When we fall we shall not be utterly cast down, for the Lord will uphold us with His hand and bring blessing out of pain.
MEDITATION PRAYER: "For thou hast delivered my soul from death: wilt not thou deliver my feet from falling, that I may walk before God in the light of the living?" (Ps. 56:13).