Albert Barnes on Matthew 28:18

All power is given unto me in heaven and in earth. The Son of God, as Creator, had an original right to all things, to control them and dispose of them. See Jn 1:3, Col 1:16,17, Heb 1:8. But the universe is put under him more particularly as Mediator, that he might redeem his people, that he might gather a church, that he might defend his chosen, that he might subdue all their enemies, and bring them off conquerors, and more than conquerors, Eph 1:20-23, 1Cor 15:25-27, Jn 5:22,23, Php 2:6-11. It is in reference to this, doubtless, that he speaks here--power or authority committed to him over all things, that he might redeem, defend, and save the church purchased with his own blood. His mediatorial government extends, therefore, over the material world, over angels, over devils, over wicked men, and over his own people.

(q) "power" Ps 2:6, 89:19, 110:1-3, Is 9:6,7, Dan 7:14, Mt 11:27, Lk 1:32 Jn 17:2, Rom 14:9, Eph 1:20,21, He 2:8, 1Pet 3:22, Rev 11:15