Come, let us take a lesson from our forefathers, and enjoy the Christmas holyday.
There are lessons to be learned from a stupid man.
When you introduce a moral lesson, let it be brief.
The poets aim is either to profit or to please, or to blend in one the delightful and the useful. Whatever the lesson you would convey, be brief, that your hearers may catch quickly what is said and faithfully retain it. Every superfluous word is spilled from the too-full memory.