The thief comes only to steal and kill and destroy; I have come that they may have life, and have it to the full.
Jesus came to give us an abundant life--in this world and, more importantly, in the one to come. A life spent for God and Jesus doesn't mean we won't have problems. In fact, it means we most certainly will have trials and problems. James tells us to give thanks for the troubles we face. They will produce the qualities we need to please the Lord.
Consider it pure joy, my brothers and sisters, whenever you face trials of many kinds, because you know that the testing of your faith produces perseverance. Let perseverance finish its work so that you may be mature and complete, not lacking anything.
I have said these things to you, that in me you may have peace. In the world you will have tribulation. But take heart; I have overcome the world.