This is very important. However most people don't even know what gratitude means. It's a very very important subject. The most important one in the torah, and everybody, even the religious people, most don't know what it means.

Gratitude does not mean that if someone does something good to you that you should be grateful. If the person had good intentions, he was kind to you. That's NOT gratitude. I'll give you an example. The torah says "Do not despise an Egyptian because you were a stranger in his land" (Devarim 23:8). It sounds absurd! Yosef saved them all from starvation and shortly after these egyptians slaughtered us, they threw the jewish babies in the river, they enslaved us for hundreds of years. According to the midrash, Pharaoh had 200 jewish children slaughtered over his bathtub each and every day so that he could bathe in their blood (that's over 700,000 kids slaughtered per year for this sick whacko!!!!). How can you have gratitude for these people! Granted they initially allowed us to dwell in their land without problems but the end of the matter is that they could not have treated us worse.

But the torah says, you have to have gratitude for them. So how do you understand that??

The answer is very very important, very fundamental. Gratitude is not because someone did something for you. But rather if you benefited, that's the keyword. If you benefited from somebody, you must have gratitude (from the book Netivei Ohr pg.165 by Rabbi Nissim Yagen). Even if the person did not have good intentions. That's why it says by Moshe that he was not allowed to hit the Nile river, to make it into blood. He had to ask Aharon to do it. A river does not care. It does not care whether he lived or died. But since Moshe benefited from the river, so then he has to have gratitude and he can't strike it. You hear?? Likewise in the talmud it says "the well that you drank from, do not throw rocks in it". Even though the well has no feelings and does not care, nevertheless since you benefited from it, you must show gratitude.

So that's very very big, The most important mitzva, and if a person has does not have a feeling of gratitude he's considered a rasha. A total rasha (thoroughly wicked person). He can't be a Jew. And the most important gratitude, do you know who it's for? Your parents! You benefited from them more than anybody. They gave you life. Ah, you might say, "well, who cares, they didn't do it for me! They were obligated to raise me."

It doesn't matter! If you benefited from them, you must have gratitude. You understand? Doesn't matter if they're good people, bad people. They did it out of niceness, or they did it because they had to. Doesn't matter. You benefited - you must have gratitude. And if you don't do it, it will damage you spiritually in proportion to how much you benefited.

One last thing, the midrash says, "every breath you take, you are obligated to thank G-d." The reason is that you're benefiting from His air. He created it. You have to thank Him for every breath. And if you don't think it's important, take your head and put it in a bucket of water and you'll see how much you're benefiting from the air.

One who contemplates this will see just how vast and all encompassing it is. The talmud says one is obligated to say "for me the world was created". Even though, this is technically incorrect. If I die, the world will continue. But since I benefit from the entire world, then I should have gratitude to G-d as if the entire world was created just for me. Scary.