In I Samuel 16, God tells Samuel to go and anoint another king over Israel. Samuel is hesitant, fearing Saul’s retribution if he does so. Then God gives him some specific instructions about what he should do, then adds in :3, “I will show you what you shall do.” Despite sharing some particulars of the plan with Samuel, God left some of them unknown. It is not uncommon for God to leave something unknown like that, so that there is always an element of faith involved when we respond to Him.
This often goes contrary to our nature. We usually tend to want to have everything figured out in advance, but that requires no faith. And remember, “Without faith, it is impossible to please Him.” (Hebrews 11:6) So God calls us (like He did Samuel here) or places us, in situations in which we must act in faith, without knowing all the details of how it is going to work out. Remember He did the same thing to Abraham in Genesis 12:1 when He told him to leave his home and “go … to the land which I will show you.” When He calls for this same kind of act of faith in your life, do not demand that everything be figured out in advance before you respond. Just go forward and obey a step at a time, and trust Him when He says, “I will show you what you shall do” when you get there!