Well I'm not truly religious, but I am a Christian with some amount of faith. I take your question seriously, so here's a few thoughts.

Sin is separation from God. Sinners choose it. The 'punishment' for sin is 'death', but my feeling is that the sin is perversely self-punishing. In other words, it's like volunteering for slavery because ... reasons?

Lying is a sin. In order to lie a person must first lie to himself. You can't give words to the lie before you've rehearsed it in your own mind. So then you lie to others, and eventually to God. So in order your sin damaged:

1. yourself
2. those you lied to
3. your relationship with God

The punishments described in The Old Testament were not assigned arbitrarily. Those being punished were doing some damnation-worthy sins at scale.