This idea comes up in Who Not How, Six Pillars of Self Esteem, & Set Boundaries, Find Peace.

I think this means your ideas are important. YOU are important. The knowledge you contain is worthy of value. You won’t violate your integrity if you take yourself seriously. This is a crucial part of self-esteem. If you don’t value your ideas, nobody else will.

From Six Pillars of Self Esteem on Self-Respect:

If we respect ourselves, we tend to act in ways that confirm and reinforce this respect, such as requiring others to deal with us appropriately.

If we do not respect ourselves, we tend to act in ways that lower our sense of our own value even further, such as accepting or sanctioning inappropriate behavior toward us by others, thereby confirming and reinforcing our negativity.

If we wish to raise the level of our self-respect, we need to act in ways that will cause it to rise—and this begins with a commitment to the value of our own person, which is then expressed through congruent behavior.

Of course this doesn’t mean you have to only take yourself seriously. It also doesn’t mean you are always right.