Midrasz do Przysłów 13:24

Now these are the names (Exod. 1:1). Scripture states (elsewhere in allusion to this verse): He that spareth his rod hateth his son; but he that loveth him chastiseth him betimes (Prov. 13:24). Normally, if a man informs his friend that someone has beaten his son, the father would deprive the guilty person even of the source of his livelihood. Why, then, does Scripture state: He that spareth his rod hateth his son? This teaches you that whenever a man fails to chastise his son, that son will ultimately act wickedly, and he will come to despise him. We find this to be so in the case of Ishmael, who behaved fondly toward his father, who failed to chastise him, and he thus went astray. As a result, Abraham began to despise him, and drove him empty-handed from his home.

And he that loveth him chasteneth him betimes (Prov. 13:24). This alludes to Abraham, who punished Isaac, taught him the law, and guided him in his ways, as it is written of him: Because that Abraham harkened to My voice, and kept My charge (Gen. 26:5). And it is also written elsewhere: And these are the generations of Isaac, Abraham’s son: Abraham begot Isaac (ibid. 25:19). This teaches us that he resembled his father in every respect; in beauty, wisdom, strength, riches, and (the performance of) good deeds. You know this to be so from the fact that though Isaac, at the time of the sacrifice, was thirty-seven years of age, and Abraham was an old man, yet he bound him and tied him as though he were a sheep, and Isaac did not resist. Scripture states: And Abraham gave all that he had unto Isaac, but unto the sons of the concubines that Abraham had, Abraham gave gifts (ibid., v. 5); that is to say, he distanced them from Isaac (so that he would have undisputed possession of the land). Hence, And he that loveth him chasteneth him betimes.