God's chosen generation
"9 But ye [are] a chosen generation, a royal priesthood, an holy nation, a peculiar people; that ye should shew forth the praises of him who hath called you out of darkness into his marvellous light: 10 Which in time past [were] not a people, but [are] now the people of God: which had not obtained mercy, but now have obtained mercy."
— 1 Peter 2:9-10 (KJV)
As children of God, we need to remember who we are and who God says we are. In this passage, we are reminded that we are chosen by God, we are royalty, and that we have come into the light. Darkness and light are used to show the contrast of our lives with and without God in them. The darkness represents our life before we accept God into our hearts when we were living without any direction and unable to see where you are going and what path you’re on. The light shows that once God was let into our hearts, our eyes were “opened” and we could see things clearly for the first time. All of this was made possible because of Jesus’ sacrifice on the cross, without that, we wouldn’t have been able to obtain God’s everlasting mercy.