“The hosts of heaven focus their worship not simply on the Lamb, but on the Lamb who was slain (Rev. 5:9). And they are still singing this song in Revelation 15:3 (“They sing the song of Moses, the servant of God, and the song of the Lamb”).
Therefore, we can infer that the centerpiece of worship in heaven for all eternity will be the display of the glory of the grace of God in the slaughtered Lamb.
Angels and all the redeemed will sing of the suffering of the Lamb forever and ever. The suffering of the Son of God will never be forgotten. The greatest suffering that ever was will be at the center of our worship and our wonder forever and ever. This is not an afterthought of God. This is the plan from before the foundation of the world.
Everything else is subordinate to this plan. Everything else is put in place by God’s providence for the sake of this plan.
The display of the glory of God’s grace, especially in the suffering of the Beloved, echoing forever in the all-satisfying praises of the redeemed, is the goal of creation and the ultimate aim of all God’s works of providence.”
–John Piper, Providence (Wheaton, IL: Crossway, 2020), 173–174.