I don’t think that there is any such thing as absolute or perfect faith for us mere mortals. Otherwise, it would be called certainty. Faith has value (to us) because it is something we must continually work on to perfect. Unlike God’s perfect gifts of Grace and forgiveness, faith is something that is earned. And it is only through our growing faith that we can truly begin to appreciate God’s gifts.
We are going to make mistakes no matter what, so it's better to be strong in faith despite our mistakes than weak in faith because of them.