This verse sits inside the father's lecture on trusting the LORD, Proverbs 3:1–12. The New Testament quotes it, with verse 12, at Hebrews 12:5–6.
Quick answer
Do not write off the LORD's correction, and do not let it make you bitter. Chastening here is training language, a father shaping a son.
Read the whole unit
The father's lecture on trusting the LORD is built with unusual symmetry: six pairs of verses, each an instruction followed by its outcome. Keep the teaching, and find long life (vv. 1–2). Bind mercy and truth to yourself, and find favor (vv. 3–4). Trust the LORD, and find straight paths (vv. 5–6). Fear the LORD instead of trusting yourself, and find health (vv. 7–8). Honor the LORD with your possessions, and find full barns (vv. 9–10). And then the pair nobody frames for the wall: do not despise the LORD's discipline, because it is the treatment sons receive from a Father who delights in them (vv. 11–12). That last pair is not an afterthought; it is the lecture's safety rail. Five pairs of blessing language could curdle into a formula, as if trust and generosity were coins for a vending machine. The sixth pair breaks the machine: the life of trust includes correction, and correction is not the system failing you. It is the Father loving you. The whole lecture describes how life tends to go inside a relationship with the LORD; it observes the grain of the world under God's active government. It does not sign contracts, and it never asks the reader to earn what the relationship already holds.
What this verse contributes
This verse names the two exits people take when correction comes: despise it as meaningless, or detest it as malice, and both misread the Father. The word behind "chastening" is musar, the discipline-as-training word this book has used since its opening verses for the whole project of forming a person. Correction belongs to formation the way pruning belongs to gardening; hating it means misunderstanding what is being grown.
Related: Hebrews 12:5–11 · Revelation 3:19
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.