In ancient times, someone's name denoted their character. Thus, God writing his name on the foreheads of the saints is indicative of us being imprinted with the very character of God. This stands in quite a contrast to our present state, when we are told in Ephesians we can (and should) but imitate God. (Ephesians 5:1) What a glorious transformation the glorified Church will undergo, when we take on the very character of our Lord! Here on earth we seek to imitate God in a childlike manor, as an infant does it's father. Rather in Heaven, by sharing in the character of God our communion and relationship with Him will be so much fuller, like when a son grows up and can reach such loftier levels of appreciation of the relationship he has with his father. In knowing that we will one day be imprinted with the very character of God, we as Christians can look with confidence and delight into the future. Our character will be improved to an extent which far exceeds our comprehension. We do not have to ponder on the hopeless despair of an inadequate character, as the absolute sufficiency of God's character awaits. And with this, our character is given purpose.. We will realize there was nothing arbitrary and meaningless about the kind of people we are, for God's ultimate goal of making us like him will reach completion.