Charles Ellicott Commentary 2 Chronicles 20:6

"and he said, O Jehovah, the God of our fathers, art not thou God in heaven? and art not thou ruler over all the kingdoms of the nations? and in thy hand is power and might, so that none is able to withstand thee." — 2 Chronicles 20:6 (ASV)

Are you not God in heaven. —So Psalms 115:2-3. Jehovah, the God worshipped by Israel, is no limited local or tribal deity, but God over all. (Compare also the first clause of the Lord’s Prayer.)

And do you not rule over all the kingdoms? —Compare 1 Chronicles 29:12 (David’s prayer), and You reign (rule) over all; and in Your hand is power and might. This and the next sentence should be rendered affirmatively, as in that place. (Compare also Psalms 47:8: God reigns over the heathen.)

So that no one is able to withstand you. —Vulgate, “nec quisquam tibi potest resistere;” Septuagint, καὶ οὐκ ἔστιν πρὸς σὲ ἀντιστῆναι. Literally, and there is no one against you to stand up. For this construction, compare Psalms 94:16: Who will stand up for me with (i.e., against) workers of wickedness. (and the last words of Asa’s Prayer, 2 Chronicles 14:11.) Syriac and Arabic, “and I am standing and praying before you.”