Hebrews 5:12-13

For indeed by this time you ought to be morim saying shiurim, but instead you have need again to be taught the orthodox Jewish basic ikarim (principles, essentials) of the Divrei HASHEM, and you have become one having need of cholov and not solid okhel. For everyone partaking of cholov is unacquainted with HaDivrei Tzedek, for he is an olel (infant).