# self-righteous, wise in your own eyes

These two phrases are combined for emphasis.

# Do not be self-righteous

"Do not think that you are more righteous than you actually are"

# wise in your own eyes

"being wise in your own opinion" or "being wise according to your own judgement"

# Why should you destroy yourself?

"There is no reason to destroy yourself." or "If you think this way you will destroy yourself."