Interpretation
The moral lesson is to avoid hypocrisy and censoriousness. The analogy used is of a small object in another's eye as compared with a large beam of wood in one's own. The original Greek word translated as "mote" (κάρφος karphos) meant "any small dry body". The terms mote and beam, more common in Early Modern English, are from the King James Version and are equivalent in modern speech to the words "speck" and "board", respectively.
A proverb of this sort was familiar to the Jews and appears in numerous other cultures too. For example, the poet Robert Burns famously wrote:
Oh, wad some Power the giftie gie us,
To see ourselves as others see us!
Read more about this topic: The Mote And The Beam