“They will be Mine,” says the LORD of Hosts, “on the day when I prepare My treasured possession. And I will spare them as a man spares his own son who serves him. — Malachi 3:17

They shall be mine,' says the Lord,'when I make up my jewels'. That's election language — we belong to Him because He chose us. Jesus prays for those the Father gave Him out of the world. He wants us to be where He is, to see His glory. He's coming to be glorified in His saints and marveled at among all who believe.