It's wrong for a person to steal.
Jake is broke and wants to take his girlfriend out to dinner and a movie.
Jake wants to get some cash.
Jake goes to his brother and asks him for a loan until he gets paid next week.
Jake finds some cash on his brother's bedroom dresser while his brother is gone and takes the cash.
Jake's brother loans Jake his requested amount and Jake is able to take his girlfriend out.
Jake's brother realizes that Jake has taken his money and confronts him, which leads to the brothers fighting.