Charles Ellicott Commentary Deuteronomy 8:5

"And thou shalt consider in thy heart, that, as a man chasteneth his son, so Jehovah thy God chasteneth thee." — Deuteronomy 8:5 (ASV)

As a man chastens his son. —This is the foundation of many similar sayings in Holy Scripture: Proverbs 13:24, He seeketh chastening for him, i.e., seeks it early. All our ideas of training necessarily imply time; it cannot be done in a moment. But the main point of the illustration is to prove God’s love. Whom the Lord loveth, He chasteneth; otherwise, why should He take the trouble to chasten at all?