Solomon
Proverbs 10:15ESV·traditional attribution

A rich man’s wealth is his strong city; the poverty of the poor is their ruin.

Matthew Henry Presbyterian @wholebiblehenry

This may be taken two ways: - 1. As a reason why we should be diligent in our business, that we may avoid that sinking dispiriting uneasiness which attends poverty, and may enjoy the benefit and comfort which those have that are beforehand in the world. Taking pains is really the way to make ourselves and our families easy. Or, rather, 2.

John Gill Reformed Baptist @doctorgill

The rich man's wealth is his strong city,.... What a fortified city is to persons in time of war, that is a rich man's wealth to him; by it he can defend himself from the injuries of others, and support himself and family in times of public calamity; for money is a defence, and answers all things, Ecc 7:12.

Jamieson-Fausset-Brown Reformed @jfbcommentary

Both by trusting in "uncertain riches" (Ti1 6:17), or by the evils of poverty (Pro 30:9), men, not fearing God, fall into dangers.