Parshas Chai Sora

When Eliezer went out to find a wife for Yitzchok, he planned a simple 'test' to see which girl would be right for Yitzchok. He would request a drink of water from a girl. If she would give him and then offer his camels to drink, she would surely be the right wife for Yitzchok.There are two middos that seemingly are the same, but are vastly different- the midda of chesed and that of rachamim. Both look the same, for both involve giving to someone anything that he lacks. Yet the difference is elementary. A baal rachamim dosn't just give out of the goodness in his heart. If a pauper comes his way he feels bad and hurt for the fellow and helps him accordingly. As much mercy as he has on the poor man, that's how much he will help him- he is there to fill the needs of others. A baal chesed on the other hand is much greater. He is someone that feels a need to give, a need to help others. This need stems from his own feeling that he must give and goes out to find people that he can do favors for. That was the middah of Avraham- chessed. On a scorching hot day he sat outside looking and running after guests- for he felt a need to give and couldn't rest unless he was helping someone else. Eliezer was looking for someone who was ready to join the house of Avraham and the most important quality she had to posses was that of chessed. He devised a plan to see if the girl was a baalas rachamim or was she on the higher level of a baalas chessed. He would ask her for a drink - if she was a baalas rachamim she would gladly offer him- a wary travler- some water to drink. But he was looking for much more. He wanted to see if she would go the extra mile and do extra for him. Would she out do her duty and find a way to give more- was she a baalas chessed? If she offered the camels a drink also, she did more then she was asked- then she was the right one to join the house of chessed.
In the zemiros of Friday night we say, דורשי יי זרע אברהם אוהבו. המאחרים לצאת מן השבת וממהרים לבא
Why do we refer to Klal Yisroel as the children of Avraham when we say that they anxiously wait for Shabbos to begin?All mitzvahs have an exact time and place when and how they can and should be done. We have no right to add or subtract fom any mitzvah. We don't have permission to do a mitzvah more then we are told to do just because we want to do more - it is baal tosef. The only mitzvah we could add to is Shabbos. We can accept Shabbos a little early and extend it a few hours into the night after nightfall- the mitzva of Tosfes Shabbos. That is the way we show Hashem that we serve him not because we are told, but rather because it's what we really want to do- our middah of chessed in doing mitzvahs. The middah of Avraham is what gave us the zechus of Tosfes Shabbos.