Note 5 at Mr 2:6: God gave us the mental faculties to be able to reason. In Isa 1:18, He invited the nation of Israel to come and reason together with Him. Paul reasoned with people using the Scriptures (Ac 17:2; 18:4, 19; and 24:25). So we see that rational thought or logic in itself is not wrong.

However, in Matthew's account of this incident (Mt 9:4), Jesus called these people's reasoning evil thoughts. Reasoning becomes evil when people fail to take into account God's revealed wisdom (the Word of God - Pr 2:1-2 and 5-6). These men would have been correct in their thinking if they had been dealing with anyone else but Jesus. The Scriptures had shown that the Messiah would take away people's sins (Isa 53:5 and 10-12), and they should have used God's Word as the basis of their reasoning (Joh 5:39).

This is where science and psychology today go astray, because they are trying to find the truth yet reject the source of all truth (Joh 14:6, 17:17; and Col 2:3). Anyone who tries to comprehend God's creation without taking God and His revealed wisdom into account is operating in evil reasoning and is a fool (Ps 10:4 and 14:1). "Professing themselves to be wise, they became fools" (Ro 1:22, see also 1Co 1:18-21 and 2:11-16).