"But you are a chosen people,a royal priesthood,a holy nation,God’s special possession,that you may declare the praises of him who called you out of darkness into his wonderful light.Once you were not a people, but now you are the people of God;once you had not received mercy, but now you have received mercy." 1 Peter 2:9-10
According to the will of God's pleasure, He made a way for us to be adopted as children by faith in Jesus Christ. He reconciled us to Himself and as believers, are apart of that family for eternity. What rich grace He has given - that we can be called "son" & "daughter".