Verse explainer
A proverb — a wise general pattern — not an ironclad guarantee. And "the way he should go" may mean according to the child's own bent, not just the parents' rules.
Train up a child in the way he should go: and when he is old, he will not depart from it.
BSBTrain up a child in the way he should go, and when he is old he will not depart from it.
The plain meaning
Proverbs are observed wisdom — reliable patterns, not absolute promises (the same book says the diligent grow rich, yet Ecclesiastes knows exceptions). This one says early, consistent formation tends to take root for life. A long-standing reading of the Hebrew phrase "in the way he should go" is "according to his way" — that is, suited to the individual child's stage and disposition. Either way it is parental wisdom, not a contract that binds a grown child's free choices or condemns every grieving parent of a prodigal.
The common misreading
What the commentators say
Henry urges early, diligent religious instruction suited to the child, expecting that habits formed young will, by God's blessing, hold in age — reading it as strong encouragement to parents rather than an unconditional warranty.
Clarke discusses the Hebrew "al-pi darko" — literally "according to his way / mouth" — and draws out the sense of training a child in keeping with the child's own capacity and stage, like initiating a young person along the path fitted to them.
Gill takes it as catechizing and habituating a child early in the right way, with the general expectation that such grounding, blessed by God, will not be wholly cast off in later life.
The word behind it
"Way, road, manner." The phrase "al-pi darko" reads literally "according to his way." Some take "his way" as the right way of wisdom; an old alternative reads it as the child's own way — his individual bent or stage. Both readings make the verse about fitted, attentive training, not a mechanical guarantee.
Related verses