Every ass thinks himself worthy to stand with the king's horses.

The proverb mocks someone who assumes they deserve a place among people regarded as more accomplished or important. The donkey’s confidence, rather than its actual standing, is the point of the comparison.

It expresses skepticism about self-importance and presumed status. The contrast between the donkey and the royal horses makes the judgment deliberately unkind, not a neutral observation about ambition.

Use it to criticize someone who claims a status or place they have not earned, especially when their confidence seems out of proportion to their abilities. Because it likens a person to a donkey, it suits a pointed or mocking remark rather than a tactful one.