The message could very well be changed to "WHO is the purpose of life?" because if we make Jesus both the first and last of our life, we can expect to find the adventure of a lifetime. Life may not be any easier than it is when God is not at the center, but it is worthwhile because at the end of it all, we can end up with Him in Heaven. That makes wondering how things will turn out on this earth not worth knowing. In fact, God specifically tells us not to look into the future. It is less important to know what is going to happen; rather it is much more important to know Who is there with us in the midst of it all.