Think of what will happen to a little child if you leave him alone. If you don’t feed him the child will starve. If you don’t talk to him or let others speak to him he won’t learn how to communicate. If you put a child near an open light bulb he might be drawn toward the pretty light and not know that he will get burned. A child is totally dependant on their parent. Likewise, as children of God, we must realize that we are totally dependant on God.
Since we are creatures we were created out of nothing. Every good thing we are given is a gift from God. When we are hungry we ourselves cannot create food out of nothing as God can. We have to rely on things of this earth (animals, wheat, fruit, etc.) which were put here by God for us. When we learn we are relying on the gifts that the Holy Spirit has given us. We cannot decide that we want to learn Latin and then suddenly know it. We must use the gifts of the Holy Spirit to learn and should pray to Him to enlighten us. In this world disorded by original sin sometimes sin may look attractive to us. We must rely on God (who alone is good MK 10:18) to show us what is good and keep us away from what is evil. As the child in the above example might cry when their parent takes him away from what he perceives as a pretty light we might question why God doesn’t allow us to do some things that our flesh is attracted to. However, since God is Truth and cannot lead us into error, we should follow His ways even if we don’t understand them or like them at the time.
Basically, it seems that Jesus is calling us to humility in this passage. We must recgonize who we are (creatures) and who God is (Creator). When we realize that we are not our own light and abandon our own will to God’s will, there will be much joy. For since God alone is good, logically His will (whether we realize it or not) is the best course of action for all involved. Once we stop questioning why God allows this and wants that and trusts that He knows what’s best for us, we will have much joy. For whatever sufferings or trials we endure we shall know that God is allowing it for the salvation of souls and treasures for us in Heaven. So we should strive to avoid asking why God allows this or wants us to do this and simply ask God what he wants of us, how we can better do His will and ask for the graces necessary to do His will.