Midrash su Malachia 2:13

R. Shaman b. Aba said: "Come and see how difficult it is to obtain a divorce, for they (the sages) permitted Abishag to be with David and did not allow him to divorce one of his wives in order to marry her." R. Eliezer said: "He who divorces his first wife, even the altar sheds tears because of him, as it is said (Mal. 2, 13) And this do ye secondly, covering the altar of the Lord with tears, with weeping and with loud complaint, so that he turneth not any more his regard to the offering, nor receiveth it with favor at your hand. And immediately after that it reads: Yet ye say, Wherefore? Because the Lord hath been witness between thee and the wife of thy youth, against whom thou hast indeed dealt treacherously; yet is she thy companion, and the wife of thy covenant."

3) Rebbi says: It was revealed before Him who spoke and brought the world into being that they were destined to balk against (the restrictions of) arayoth, wherefore He confronted them with a decree: "I am the L–rd your G d" — Know who decrees (these strictures of arayoth) upon you! And we find similarly that they balked against arayoth in (Bamidbar 11:10) "And Moshe heard the people weeping over their families" (i.e., against the restrictions of illicit relations). And thus did Malachi say to them (Malachi 2:13) "And this you do a second time: covering the altar of the L–rd with tears, with weeping and with sighing." He said to them: This is not the first time (you weep so.) You already wept (over this) in the days of Moses. They answered (Malachi 2:15) "And did not One do (this) and He is noble of spirit!" Did not He who created Israel create the (other) peoples? (Why, then, can we not intermingle with them!) To this he replied (Malachi 2:15) "And what is it that this 'One' desires, (but) the seed of G d!" (and not of the nations) — at which they all responded (Malachi 2:12) "Let the L–rd cut off from the man that does this a quick one and an answerer from the tents of Yaakov" — Let him not have "a quick one" among the sages nor "an answerer" among the disciples — And, if he were a Cohein, (Malachi 2:12) "or a presenter of a meal-offering to the L–rd of hosts." And thus is it written (re the materialization of such intermingling, Nechemiah 13:29) "And one of the sons of Yoyada, the son of Elyashiv the high-priest, was son-in-law to Sanvalat the Choronite."

"Upon the Torah," whence do we know (this)? Because it is written, "If my covenant of day and night stand not" (Jer. 33:25); and (another text) says, "This book of the Torah shall not depart out of thy mouth, but thou shalt meditate therein day and night" (Josh. 1:8). Whence do we know (that the world rests) upon the service of loving-kindness? Because it is said, "For I desired love, || and not sacrifice" (Hos. 6:6). Whence do we know (that the world rests) upon Divine Worship? Because it is written, "And the prayer of the upright is his delight" (Prov. 15:8).