Christians live in "already but not yet" time. The kingdom of God is already here through Jesus’ life, teaching, death, and resurrection. It is present today in this world and it is spreading like "yeast" (Matt 13:33). At the same time, the full manifestation of the kingdom is not here yet. It will be fully established in the eschaton, on the end of the day when Jesus returns with his angels to redeem all the believers and renew everything. So, as the church witnesses and participates in God’s kingdom, we know that it is imperfect.