We know God is just because His actions and judgments reflect His perfect righteousness, as indicated in Genesis 18.
God's justice is foundational to His character; He cannot act contrary to His nature. In Genesis 18, Abraham asserts that it would be far from God to treat the righteous as the wicked, affirming that the judge of all the earth will do right. This belief is not merely a philosophical concept but is rooted in the nature of God Himself. His judgments are always fair, and He ensures that everyone receives what is due according to their deeds.
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