Midrash su Deuteronomio 16:14

(Fol. 8b) MISHNAH: No marriages may take place during the festival week, neither of virgins nor of widows; nor may one marry a Yebama [the childless widow of his deceased brother], as it is a cause of joy to him. But one may remarry his own divorced wife. GEMARA: And even if it is a cause of joy to him, what of it? R. Juda said in the name of Samuel, and so also did R. Elazar say in the name of R. Oshiya, and according to some in the name of R. Chanina: "Because you must not mix one joy with another." Rabba b. Huna said: "Because he might neglect the enjoyment of the festival on account of his rejoicing over his wife." "The statement of Rabba R. Huna," remarked Abaye to R. Joseph, "was originally made by Rab; for R. Daniel b. K'tina said in the name of Rab: 'Whence do we learn that it is not permitted to marry during the festival week? It is said (Deut. 16, 14) And thou shall rejoice on thy feast; i.e., Over thy feast thou shalt rejoice, but not over thy wife.'" Ula said: "The reason is, because there would be too much trouble [to prepare for the wedding]." R. Isaac Nafcha said: "The reason is, in order that all marriages should not be postponed until a festival."

(Esth. 8, 16) For the Jews there was light, and joy and gladness and honor. R. Elazar, in the name of R. Juda, said: "Light, refers to the Torah, and so says the passage (Prov. 6, 23) For the commandment is a lamp, and the law is light. Joy, refers to a holiday, and so says the passage (Deut. 16, 14) And thou shalt rejoice in thy feast; gladness, refers to circumcision, and so says the passage (Ps. 119, 162) I am rejoiced over thy promise; honor, refers to Tephilin, and so says the passage (Deut. 28, 16) And all the nations of the earth shall see that thou are called by the name of the Lord, and they shall he afraid of thee. And we are taught in a Baraitha: R. Eliezer the Great said: 'This refers to the Tephilin on the head.' "

(Fol. 27b) Our Rabbis were taught: It once happened that R. La'yi went on a festival to Lud to pay his respects to his teacher R. Eliezer. "La'yi, art thou not of those who rest on the festival?" R. Eliezer asked him; for R. Eliezer used to say: "I praise the sluggards, who do not leave their houses on a festival, for it is said (Deut. 16, 14) And thou shalt rejoice in thy feast, etc." Is this so? Did not R. Isaac say: "Whence do we learn that a man must pay respects to his teacher on the festival by visiting him? It is written (II Kings 4, 23) Wherefore art thou going to him to-day? It is neither new moon nor Sabbath? From this we infer that on a new moon and a Sabbath it is a duty for every one to visit his teacher." This is not difficult to explain: the latter deals with a case where one can go and return the same day [when the teacher lives in the same city]; and the former deals with a case where one cannot return on the same day [one should prefer the reunion with his family].