Matthew Poole and continuators on Genesis 37:3

3 Now Israel loved Joseph more then all his children; because he was the son of his old age : and he made him a coat of many colours .

Being born when Iacob was Ninety one years old. Such Children are commonly best beloved by their Parents, either because such are a singular blessing of God, and a more then common testimony of his favour, and a mercy least expected by them and therefore most prized; or because they have more pleasing conversation with them, and less experience of their misbehaviour, of which the elder oft times are guilty, whereby they alienate their Parents affections from them. The antient Translations, Chaldee, Persian, Arabick and Samaritan, render the words thus, a wise or prudent son, old age being oft mentioned as a token of prudence, one born old, one wise above his years, one that had a gray head, as we say, upon green shoulders. This may seem the more probable, both because Ioseph was indeed such a Child, and gave good evidence of it in a prudent observation of his brethrens trespasses, and a discreet choice of the fittest remedy for them; and because the reason here alledged seems proper and peculiar to Ioseph, whereas in the other sense, it belongs more to Benjamin, who was younger then Ioseph, and cost his Mother dearer, and therefore might upon that account claim a greater interest in his Fathers affections.

Probably made of threds of divers colours interwoven together. Compare 2 Sam. 13. 18. This he gave him as a token of his special love, and of the rights of the first-born, which being justly taken from Reuben he conferred upon Ioseph, 1 Chron. 5. 1.

Marginal references: Or, pieces. Judg. 5. 30. 2 Sam. 13. 18.