Niddah

GEMARA. Our Rabbis taught: Although [the Sages] have said, 'He who has intercourse in the light of a lamp is contemptible',  Beth Shammai ruled: A woman needs two  testing-rags for every intercourse  or she must perform it in the light of a lamp, but Beth Hillel ruled: Two testing-rags suffice for her for the whole night. It was taught: Beth Shammai said to Beth Hillel, 'According to your view  is there no need to provide against the possibility that she might emit  a drop of blood of the size of a mustard seed in the course of the first act and this would be covered up with semen during the second act?'  'But', replied Beth Hillel, even according to your view  is there no need to provide against the possibility that the spittle,  while still in the mouth,  was crushed out of existence?'  '[We maintain our view,] the former retorted, 'because what is crushed once is not the same as that which is crushed twice'. It was taught: R. Joshua stated, 'I approve  of the view of Beth Shammai'.  'Master', said his disciples to him, 'what an extension [of the restrictions] you have imposed upon us!' 'It is a good thing', he replied, 'that I should impose extensive restrictions upon you in this world in order that your days may be prolonged in the world to come. R. Zera remarked: From the words of all these authorities  we may infer  that a conscientious man should not indulge in intercourse twice in succession.  Raba said: One may indulge in intercourse twice in succession, for that ruling  was taught only in respect of clean objects.  So it was also taught: This  applies only to clean objects  but to her husband she is permitted.  This,  however, applies only where he had left her in a state of presumptive cleanness, but if he left her in a state of presumptive uncleanness she is presumed to be in that state forever until she tells him, 'I am clean'. R. Abba citing R. Hiyya b. Ashi who had it from Rab ruled: If a woman  examined herself with a testing-rag which was subsequently lost she is forbidden intercourse until she had reexamined herself. R. Ela demurred: If it had not been lost  would she not  have been allowed intercourse even though she is unaware [whether there was or there was not a discharge], why then should she not now also  be allowed intercourse? — Raba replied: In the former case her proof is in existence,  but in the latter case  her proof is not in existence. R. Johanan stated: It is forbidden to perform one's marital duty in the day-time.  What is the Scriptural proof? That it is said, Let the day perish wherein I was born, and the night wherein it was said: 'A man-child is brought forth'.  The night is thus set aside  for conception but the day is not set aside for conception. Resh Lakish stated: [The proof is] from here: But he that despiseth His ways  shall die.  As to Resh Lakish, how does he expound R. Johanan's text?  — He requires it for the same exposition as that made by R. Hanina b. Papa. For R. Hanina b. Papa made the following exposition: The name of the angel who is in charge of conception is 'Night', and he takes up a drop and places it in the presence of the Holy One, blessed be He, saying, 'Sovereign of the universe, what shall be the fate of this drop? Shall it produce a strong man or a weak man, a wise man or a fool, a rich man or a poor man?' Whereas 'wicked man' or 'righteous one' he does not mention, in agreement with the view of R. Hanina. For R. Hanina stated: Everything is in the hands of heaven except the fear of God, as it is said, And now, Israel, what doth the Lord thy God require of thee, but to fear etc.  And R. Johanan?  — If that were the only meaning,  Scripture should have written,  'A man-child is brought forth'  why then was it stated, 'was brought forth a man-child'?  To indicate that the night  is set aside for conception  but the day is not set aside for conception. As to R. Johanan how does he expound the text of Resh Lakish?  — He requires it for [an application to the same types] as those described in the Book of Ben Sira:  'There are three [types] that I hate, yea, four that I do not love: A Scholar  who frequents wine-shops  [or, as others say, a scholar that is a gossip],  a person who sets up a college in the high parts of a town,  one who holds the membrum when making water and one who enters his friend's house suddenly'.  R. Johanan observed:  Even his own house. R. Simeon b. Yohai observed: There are four [types]  which the Holy One, blessed be He, hates, and as for me, I do not love them: The man who enters his house suddenly and much more so [if he so enters] his friend's house, the man who holds the membrum when he makes water,