How does adopting a religion change a person's life?

Ethics can change your course of action.

Only the Catholic Church has the fullness of truth.  By joining the Catholic Church a person gives himself a chance at salvation.

Mostly it gives you an excuse to feel superior to somebody and puts an identity on the people you are supposed to hate.

 Its sends them crazy

It starts witn Dan. 10:12 and goes on from there.

I don't know.  I've never adopted a religion.

Every Christian I have ever met, without exception, is:

1. An alcoholic (see Fireball for an example), or

2. Abusing drugs, or, 

3. Mentally ill or severely depressed.

It sure changes a person's life, but I would advise staying away from it.

Most religions set the way a person ought to live to please God.  For instance, Judaism, Christianity, and Islam, each claim to worship the God of heaven and earth, yet because of the way in which their devotion to God is presented, their lifestyle is vastly different.