Why is this wrong?

2. R. Jose of Milhayal and R. Joshua of Siknin in the name of R. Levi said: We find that children in David's days, before they had yet experienced the taste of sin, knew how to expound the Torah by adducing forty-nine reasons for declaring a thing unclean and forty-nine reasons for declaring it clean, and David prayed for them. This is the import of what David says: Thou O Lord keep them (Ps. XII, 8), meaning: Do Thou, O Lord, preserve their learning in their hearts! Thou wilt preserve us from this generation for ever (ib.), namely, from this generation which deserves extermination.2 Yet after all this praise3 they used to go out to battle and fall! It was only because there were informers among them that they fell. This is the import of what David says: My soul is among lions (Ps. LVII, 5). ’Lions’ applies to Abner and Amasa who were lions in the Torah.4 I do lie down among them that are aflame--lohatim  (ib.); this applies to Doeg and Ahitophel who were burning  (lehutim) to spread slander. Even the sons of men, whose teeth are spears and arrows (ib.). These are the men of Keilah of whom it is written, Will the men of Keilah deliver me up into his hand (I Sam. XXIII, 1)? And their tongue a sharp sword (Ps. loc. cit.) applies to the Ziphites, of whom it is written, When the Ziphites came and said to Saul: Doth not David hide himself with us? (ib. LIV, 1). On that occasion David exclaimed: What with all this is the Shechinah doing on earth? Be Thou exalted, O God above the heavens (ib. LVII, 6); as much as to say: Remove Thy Presence from their midst! The generation of Ahab, however, were all worshippers of idols, yet owing to the fact that there were no informers among them they used to go out to war and be victorious. This is borne out by what2. R. Jose of Milhayal and R. Joshua of Siknin in the name of R. Levi said: We find that children in David's days, before they had yet experienced the taste of sin, knew how to expound the Torah by adducing forty-nine reasons for declaring a thing unclean and forty-nine reasons for declaring it clean, and David prayed for them. This is the import of what David says: Thou O Lord keep them (Ps. XII, 8), meaning: Do Thou, O Lord, preserve their learning in their hearts! Thou wilt preserve us from this generation for ever (ib.), namely, from this generation which deserves extermination.2 Yet after all this praise3 they used to go out to battle and fall! It was only because there were informers among them that they fell. This is the import of what David says: My soul is among lions (Ps. LVII, 5). ’Lions’ applies to Abner and Amasa who were lions in the Torah.4 I do lie down among them that are aflame--lohatim  (ib.); this applies to Doeg and Ahitophel who were burning  (lehutim) to spread slander. Even the sons of men, whose teeth are spears and arrows (ib.). These are the men of Keilah of whom it is written, Will the men of Keilah deliver me up into his hand (I Sam. XXIII, 1)? And their tongue a sharp sword (Ps. loc. cit.) applies to the Ziphites, of whom it is written, When the Ziphites came and said to Saul: Doth not David hide himself with us? (ib. LIV, 1). On that occasion David exclaimed: What with all this is the Shechinah doing on earth? Be Thou exalted, O God above the heavens (ib. LVII, 6); as much as to say: Remove Thy Presence from their midst! The generation of Ahab, however, were all worshippers of idols, yet owing to the fact that there were no informers among them they used to go out to war and be victorious. This is borne out by what Obadiah said to Elijah: Was it not told my lord... how I hid a hundred men of the Lord's prophets... and fed them with bread and water? (I Kings XVIII, 13)-If he mentions bread why also water?’ The reason can only be that it teaches that the water was more difficult for him to obtain than the bread-yet Elijah proclaims on Mount Carmel, saying: I, even I only, am left a prophet of the Lord (ib. 22), and all the people know the real circumstances2 and do not announce it to the king! R. Samuel b. Nahman observed: The serpent was asked: ' Why are you generally to be found among fences?’ He replied: ‘Because I made a breach in the fence of the world.’3 R. Simeon b. Yohai learned: The serpent was the first to make a breach in the world's fence, and so he has become the executioner of all who make breaches in fences.4 The serpent was asked: ‘Why do you bite? What do you gain thereby? The lion tears his prey and eats it, but you simply bite and kill!’ He answered: ’ Doth the serpent bite without a whisper (Eccl. X, 11)?5 Is it conceivable that I should do anything unless instructions were given me from on high? ' He was asked: ‘How is it that you bite into one limb and your poison travels to all the limbs? ' He answered: ' Do you say this to me? The master of the tongue6 hath no advantage (ib.), for he can dwell in Rome and slay in Syria, or dwell in Syria and slay in Rome.’7 Why is a slanderer called ‘third ‘?8 Because he kills three, viz. the one who utters it, the one who listens to it, and the one about whom it is spoken. An incident is related of a man who had a wicked daughter-in-law who was addicted to slander. He used to plead with her twice a day, once in the evening and once in the morning. He would say to her: ‘I beg of you not to
speak slander!’ What did she do? She went and told her husband: ' This father of yours wants to cohabit with me; and if you do not believe me come in at night and you will find him sitting and soliciting me.’ He went and lay in wait for him and saw him leaning over her and conversing with her. ' The thing,’ he said, ' is true then! ' What did he do? He struck his father and killed him. He was brought to justice and was sentenced to death. That woman also, who had spoken slander about his father, was brought to justice and sentenced to death. Thus it happened that the tongue killed the three of them.