What does Proverbs 12:3 mean?

This verse teaches that evil behavior, by its own nature, can never bring a person to a place of stability and peace. It cannot "establish" anything but the expectation of judgment. The book of Proverbs makes multiple references to the ultimate fate of those who defy God (Proverbs 9:13–18; 11:7), in contrast to those who follow Him (Proverbs 1:7).

Likely, Solomon had in mind the Israelites' occupation of the Promised Land. The Lord had promised to keep them in the Promised Land if they obeyed Him. However, He assured them they would be uprooted if they worshiped false gods and refused to obey His commandments (Deuteronomy 31:15–20). Unfortunately, the people of Israel failed to worship and obey the Lord. Centuries later, after failing to observe the Sabbath years and to worship only the Lord, they were exiled by the cruel Babylonians, and spent 70 years in Babylon.

A modern application of this statement is assurance. Believers may be discouraged under persecution, or when seeing evil people enjoying temporary prosperity (Psalm 73:2–3). Followers of Christ can take comfort in knowing that blessing comes to the righteous, whereas punishment comes to the wicked (Hebrews 4:13; Revelation 20:11–15). Believers are secure in the Lord's hands.