I would have said that sometimes it's very important for employers to learn how to speak to there workers. some time ago I have heard of people complaining how they have been treated as slaves to there employers, and I have come to find out that most are truths because I witnessed same event with some people recently, and into employees should also try to accept things politely hence issues of employers harassing employees would reduces.
Back to your story, its unfortunate that some people are just ingrates, they sometimes cause people to have misfortune because pf there stupid acts. with the experience your employer has gotten from your friend psychologically he or she might not be able to employ others based on experience, thereby your friend has become a difficulty to others.
Its said that opportunities comes but once and at this your friend ahs missed another opportunity because of his wrong did. there is no advise that will be give to an adult that will have an impact on them except they have accepted in their hearts to change so you would be able to advise your friend and he will accept it, just do your best for him and let him do his part for his life because every body has his or her own goal to reach.
I told him that it is January and there is vacancy he should go and plead again he went and he was employed but he went back and stole two months after he was employed and he was given the highest salary among all new workers as a person who already knew the work operation.
I can't understand this clearly can you please expansiate a little more.