As God begins to warn Judah through the prophet Isaiah and plea for them to remain faithful to Him, He makes this familiar statement, “Come now, and let us reason together” (Isa. 1:18). God makes His “reasoned” case through Isaiah and expected the people to understand and reason correctly back into a right relationship with Him.
While many today suggest that truth is relative and everyone has their own truth, that does not match in any way what the God of truth (Isa. 65:16) reveals to us. Jesus said that there is “the truth” (objective, not subjective) and that man would be able to “know” it (John 8:32). While children have not developed the ability to know the difference between “good and evil” (Deut. 1:39; Jon. 4:11), as individuals mature, and especially as they engage with God’s Word, they will “by reason of use have their senses exercised to discern both good and evil” (Heb. 5:14).
God expects us to use the brains He has given us to reason, but not just to reason, but to reason correctly, according to His Word (1 Sam. 12:7; Acts 17:2; 24:25; 26:25; 1 Pet. 3:15).