The surprise element in the proverb is that the servant who is not descended from the master of the house eventually becomes the successor, the heir, and in effect the son who continues the family good name. How could such a great promotion take place? The thought is similar to Proverbs 17:2.
Here is a beautiful picture of the transformed relationship which every Old Testament saint and every true Christian has with his God. Christ says to his disciples, ‘Henceforth I call you not servants; for the servant knoweth not what his lord doeth: but I have called you friends; for all things that I have heard of my Father I have made known unto you’ (John 15:15). Unbelievers are certainly servants or even slaves by nature before conversion. By what amazing grace are we brought into the family of God by adoption! The new birth transforms our status so that we are now sons and daughters of the living God and heirs according to the promise. But we do not forget that we did not start off as children of God. We began life under the law and having no permanent place in the house as Christ says, ‘The servant abideth not in the house for ever: but the Son abideth ever’ (John 8:35). Old Testament Israelites under the law were not truly sons but more like servants. Emancipation came for the individual Israelite when he or she trusted in Christ and looked to him for justification and imputed righteousness. Every true believer has undergone this amazing journey from slavery to sonship and each one is a demonstration of the grace of God.
Two different words in this verse occur only here in the Bible: the word translated ‘delicately bring up’ and the word translated ‘his son’. The first is rendered ‘pampers’ by many versions but, depending on the view taken of the verse as a whole, it should to have a more positive connotation than that word implies in current English. The servant is not being spoiled or molly-coddled, but receives great attention and skilful nurturing from the father of the house. The second is thought by some to have the opposite meaning of ‘ungrateful’ and this gives a wholly negative sense to the verse, teaching the bad outcome that follows overindulgence of a servant, who presumably should be kept at a greater social distance from the master. The rendering ‘his son’ arises from a connection with the Hebrew word meaning to continue, to increase, to propagate. There is clearly much more of the element of surprise, which Solomon is so fond of, in the second of these alternatives, and a meaning connected with the theme of preparing the next generation fits the context better.