there is this phrase we use in theology to talk about the promises of God that have be partcially fulfilled but have not yet been realized in all their glory (already/not yet)...for example the word shalom represents a vision of wholistic blessing of life abunant, while we encounter moments and spaces of shalom we do not fully live in a place where this exists as it was intended to exist, through out the whole of humanity and created order.
i find that this term also applies to other things in daily life...say for my friends Jesse & Erika who were engaged for a month and a half before they got married last friday. while they were engaged they lived in the already/not yet state of marriage being committed to someone but not yet fully having the rights and priveldges of a married couple in the eyes of others and the law. i think often this already/not yet status is a part of transitions and relationships. like summer transitions from one grade to another...when i saw my godchildren last week they were talking about school and what grades they are going into the next fall. i remember how cool it was at the end of your last day of school to say as you were running out the door i'm no longer a 4th grader i am now a 5th grader even though you actually don't start class for another three months.
often we live this space of things that we hope for but have not had fully realized. that waiting is hard it's like having a vision before the reality of that vision comes. and this is the already not yet of life