Vayeirah via Shemen HaTov

The Torah says that Avraham offered much hospitality and abundant food to his guests. However (Breishit 17:4) when it comes to water to wash with he asked them to take "a little water." Rashi comments on his offer to take water, saying that this was done by way of a worker, on Avraham's behalf. Perhaps Rashi is answering the question of why he only gave them a bit of water. Avraham was in the desert, water was not easy to come by.  He had someone get it for him.  He did not want to burden the go between who got water for him, even though he went all out on all other fronts.  Perhaps the lesson here is that we can go all out when it is at our own expense.  But we should be careful of being kind at someone else's expense.