Charles Ellicott Commentary Ecclesiastes 7:12

"For wisdom is a defence, even as money is a defence; but the excellency of knowledge is, that wisdom preserveth the life of him that hath it." — Ecclesiastes 7:12 (ASV)

A defense— Literally, a shadow (Psalms 91:1; Psalms 121:5, and other similar passages). This verse harmonizes with the interpretation of the preceding verse, which we prefer. “Wisdom and riches alike confer protection, but the pre-eminence of wisdom is...”