What is dishonesty? In one's desire for wealth and honor, one makes evil good by associating with both passion-lust and bewilderment-erring. It provides an obstacle for getting good counsel.
It is the intent to conceal one's shortcoming from others because one is so attached to wealth and honor.
Nowadays, people like us try to keep our mistakes a secret, but when others find out our hidden secret, we become meek and prudent; ultimately we deceive ourselves.
One should think about this matter over and over again as stated in the Bodhicaryavatara,
I am constantly living
Under the watchful eyes of
The Buddhas and Bodhisattvas
Who have unlimited vision.
Thinking in this way, I should consider
Self-respect, devotion, and apprehensiveness.
These two, deceit and dishonesty, hinder the obtaining of good counsel in this life and in the next one, and they set up various forms of unpleasantness such as not meeting spiritual teachers in the Mahayana. Therefore, these two are counted among the four bleak things referred to in the Kasyapaparivarta.
1. To lie to one's teacher, guru, or monk
2. To produce regret in the minds of others who have no regret
3. To speak words which neither praise nor glorify nor explicate those who truly seek the Mahayana path
4. To praise others with dishonesty and deceit and without a pure feeling