The New Testament teaches that God is building a spiritual house made up of believers who were once dead in their sin but this isn't a dead house, it's a house full of life because it's members have been made alive in Christ.
Within this context Paul then prays that we would know in our Inner Being how vast God's love is towards those who believe in HIm.
All are invited into such a compelling relationship with God so that He would have 'A People' The People of God who once were dead but now get to enjoy God forever.