Musar zu Schemuel II 6:12

Come and see the greatness of the eminence of one who upholds the Torah, and benefits a Torah scholar with his possessions and draws close to him, Scripture considering it as if he [thereby] cleaved to the Shechinah. As Chazal (Kethuvoth 111a) say on the verse (Deuteronomy 4:9): "And you that did cleave to the L-rd your G-d are all alive this day." Now is it possible for a man to cleave to the Shechinah? Is it not written (Ibid. 24): "For the L-rd your G-d is a consuming fire!" The intent is, rather, if one weds his daughter to a Torah scholar, or does business for a Torah scholar, or benefits a Torah scholar with his possessions, it is accounted to him as if he cleaved to the Shechinah." And they stated further (Ibid. 10b): "All who lodge Torah scholars in their homes and offer them of their fare are regarded by Scripture as presenters of daily ['continual'] sacrifices." And (Ibid. 63b): "R. Nechemiah opened [his discourse] in honor of the host, expounding (I Samuel 15:6): 'And Saul said to the Keni: Go, depart, go down from the midst of Amalek, lest I destroy you with him — and you have done lovingkindness with all the children of Israel': Now does this not follow a fortiori? If Yithro, who befriended Moses only for his own honor had this accorded [to his descendants, the Keni], then one who is host to a Torah scholar, and feeds him, and gives him to drink, and treats him of his possessions, how much more so!'… R. Elazar b. R. Yossi Haglili opened [his discourse] in honor of the host, expounding (II Samuel 6:11): 'And the L-rd blessed the house of Oved-Edom… because of the ark of G-d' [which he kept in his house]. Now does this not follow a fortiori? If the ark, which did not eat and did not drink — because they swept and sprinkled before it, thus [were they rewarded], then one who is host to a Torah scholar, and feeds him, and gives him to drink, and treats him of his possessions, how much more so!'"