The gemara says that one who smiles to another is better than giving him milk. I find this metaphor very puzzling - Why is smiling compared to giving someone a drink (even if fulfilling his thirst)? Why is it even better than doing so? And why is milk chosen? I looked at some of the classic commentaries like Marsha but could not seem to find anything. Can you please point me to other insights to this comment of our rabbis?
binyamin, new york
Bear in mind that the D'rashah under discussion is taken out of context. What the Pasuk is really saying is that there will be such an abundance of milk in the portion of Yehudah that it will cause their teeth to become white (an indication of the good quality of the pasture-lands).
What the Gemara in Kesuvos does is to make an independant D'rashah from the whiteness of the teeth (i.e. a smile) and milk. The message is that despite the abstract nature of a smile, and its quick passing, it is more valuable that a cup of milk (a gift of substance that lasts longer than a smile and would seem to be more satisfying).
To be sure, the same can be said about a cup of wine, vodka or coke, but since the Pasuk is talking specifically about milk, Chazal convey the message via a cup of milk.
Be'Virchas Kol Tuv