On the twenty-eighth day of Adar there came good news to the Jews. The Roman Government had passed a decree ordaining that they should neither study the law, nor circumcise their children, nor observe the Sabbath-days. Yehudah ben Shamua and his associates went to consult a certain matron, whom all the magnates of Rome were in the habit of visiting. She advised them to come at night and raise a loud outcry against the decree they complained of. They did so, and cried, "O heavens! are we not your brethren? are we not the children of one mother?" (Alluding to Rebekah, the mother of Jacob and Esau.) "Wherein are we worse than all other nations and tongues, that you should oppress us with such harsh decrees?" Thereupon the decrees were revoked; to commemorate which the Jews established a festival.
The renewal of the moon comes round in not less than twenty-nine days and a half and forty minutes.
Rav Mari reports that Rabbi Yochanan had said, "He who indulges in the practice of eating lentils once in thirty days keeps away quinsy, but they are not good to be eaten regularly because by them the breath is corrupted." He used also to say that mustard eaten once in thirty days drives away sickness, but if taken every day the action of the heart is apt to be affected.
He who eats unripe dates and does not wash his hands will for thirty day be in constant fear, without knowing why, of something untoward happening.
The Rabbis have taught that the lighter kind of excommunication is not to last less than thirty days, and censure not less than seven. The latter is inferred from what is said in Num. xii. 14, "If her father had but spit in her face, should she not be ashamed seven days?"
If we meet a friend during any of the thirty days of his mourning for a deceased relative, we must condole with him but not salute him; but after that time he may be saluted but not condoled with. If a man (because he has no family) re-marries within thirty days of the death of his wife, he should not be condoled with at home (lest it might hurt the feelings of his new partner); but if met with out of doors, he should be addressed in an undertone of voice, accompanied with a slight inclination of the head.