One of the book's great reversals of what strength means.
Quick answer
Self-mastery outranks conquest: the person slow to anger stands above the war hero, because the hardest territory anyone governs is internal.
Read both lines
The comparison would have scandalized its first hearers: the city-taker was the ancient world's maximum human, and the proverb sets the slow-to-anger above him. The logic holds under inspection: a city's walls are outside you and fall once; your own spirit must be governed every day, under provocation, without applause. Many have done the first without the second. The verse also reveals what God counts impressive: slow to anger, erek appayim, is the LORD's own advertised trait (Exodus 34:6, the NKJV's "longsuffering"), so ruling your spirit is resembling Him at the exact point where the mighty usually do not.
Related: Proverbs 14:29 · Proverbs 25:28 · Exodus 34:6 · James 1:19–20
New King James Version®, Copyright © 1982, Thomas Nelson. All rights reserved. Full copyright information. Scripture provided by API.Bible.
Go Deeper
If this verse has been used to put weight on you that it was never carrying, ask about it directly.