We all get discouraged from time to time, especially when we can't do something we want to do, or we find our way blocked and life becomes difficult. Then we become like Job in the Old Testament: "Trouble comes to you, and you are discouraged; it strikes you, and you are dismayed" (Job 4:5).
Is it a sin to be discouraged? Not necessarily, although it can be if it leads to anger or makes us stop doing something God wants us to do. And we need to understand that it's not always a brief or temporary problem; sometimes discouragement takes root in our hearts and minds, and pulls us down for years. Parents get discouraged with their children; workers get discouraged with their jobs; sick or elderly people get discouraged about their future -- the list could go on and on.
Did Jesus ever get discouraged? Perhaps not in the sense we usually mean it, but He certainly was burdened over people's failure to repent and turn to God. He wept over those who refused to turn to God in repentance and faith. In the last hours before His arrest and trial, He cried out, "My soul is overwhelmed with sorrow to the point of death" (Mark 14:34).
The real question, however, is this: What should we do when we become discouraged? The answer is to turn to God and His Word for the strength and encouragement we need. Let God's words to Joshua become yours: "Be strong and courageous. Do not be afraid; do not be discouraged, for the Lord your God will be with you wherever you go" (Joshua 1:9).