Welcome to Qatar. This is the usual line of cowards who don't know how to be proper bosses here; they simply resort to bullying and threats to get the job done. This shows in the level of customer service, construction quality, etc. in Doha. You don't get good results from workers by threatening them. Sadly, they CAN send you home rather easily, so calling their bluff doesn't do you very good. The next time he threatens to send you home, say something like "Good. I would rather be poor and hungry in my own country than be treated like a slave and have to work with a moron like you", then go pack your bags.

The bosses learn from THEIR bosses, and this is they way the locals's talk to their workers and handle their problems as well, they simply send them back home. They threaten the lower bosses the same way, and the bosses threaten you with it. In summary, there's nothing you can do about it.

I like how some of the people answering here are accusing you of not being a good worker. I've been in Qatar long enough to know it doesn't matter how many hours you work, how hard you work, how much free-time you give up, and how little you earn; it is never enough and you will always be treated poorly and threatened with deportation. They have the upper hand, and you have to get used to it.

All you can do is someday hope to meet your "boss" in a bar in your own country some night, as equals, and you can tell him what you really think of him.