There are examples of the use of modal verb MAY in proverbs, sayings and quotations.

Proverbs

1. A cat may look at a king.
2. Cowards may die many times before their death.
3. A fair face may hide a foul heart.
4. Bitter pills may have blessed effects.
5. Be careful what you wish for, you just might get it.
6. Hares may pull dead lions by the beard.
7. The remedy may be worse than the disease.
8. Sticks and stones may break my bones, but words will never hurt me.
9. When the oak is before the ash, then you will only get a splash; when the ash is before the oak, then you may expect a soak.
10. If you don�t like it you may lump it.
11. Between the cup and the lip a morsel may slip.