In someone else's eye we see a speck, but in our own log we do not notice this is a proverb about self-deception. Especially well their sins are visible in other people, but in themselves are not visible.
A log in your own eye isn't as bad as it looks. Indeed, we are able to see only the vices and sins that are in us, but this is for the best. Vices and sins in small quantities we need as inoculations. The invisible enemy is especially dangerous, it can very slowly creep up to us and slowly eat us, or we can eat it, get poisoned and infected, and die in terrible agony.