Exactly. Beliefs have impact. It changes our behaviour / lives.
All the more reason to stay clear of faith (belief on bad or no evidence) and consider rational justification (belief on independently verifiable evidence) important.
There is nothing irrational about avoiding that which G-d has made unlawful
Except for the fact that there is zero evidence that there is a god and even if there is, there is zero evidence that the claims about what he / she / it made unlawfull actually comes from him / her / it.
It's as irrational as avoiding that which the extra-dimensional unicorn, or any other unfalsifiable and unsupportable entity, has "made unlawfull".
There is nothing irrational about establishing worship, which brings order into our lives, and G-d's help.
Except when it's done on bad or no evidence. Which incidentally is the case for all religions.
Evil is defined in a general sense, by what it is not—the opposite or absence of good. It can be an extremely broad concept, although in everyday usage it is often more narrowly used to talk about profound wickedness.
I observe that people are capable of evil, and have experienced temptation myself.
Why deny the truth?
Far more people don't engage in "evil" then those that do.
The vast majority of people do not rape, murder, steal, mutilate, abuse, ....
So to say that humans have a "natural inclination" to do evil, is just demonstrably incorrect.
If it were true, most people would engage in evil.
But most don't.
It's one of those things religions tend to say to put humans on a guilt trip and have them kneel down to whatever god the religion in question is claiming.