Midrasch zu Jeschijahu 8:14

Juda and Hezekiah, the sons of R. Chiya, were sitting at a banquet before Rabbi [the Nassi] and did not utter a word. The Rabbis remarked: "Let the wine get the better of the youngsters (let them become a little merry), so that they shall say something." As soon as they were filled with wine they began sayiug: "Ben David will not come until there will be an end to the two families (dynasties), that of the Babylonian Exilarchs and that of the Princes of Palestine, as it is said (Is. 8, 14) And he will be for a sanctuary; but also for a stone of stumbling, and for a rock to fall over unto the two houses of Israel." Whereupon Rabbi exclaimed: "Children! you are throwing thorns in my eyes!" "Rabbi," remarked they "Yayin (wine) amounts numerically to seventy, and the word Sod (secret) amounts to seventy, hence as soon as wine enters the secret goes out." R. Chisda lectured: "What is the meaning of the passage (Dan. 9, 14) Therefore was the Lord hurried to bring the evil, and He brought it upon us; for the Lord our God is righteous; i.e., is it because the Lord our God is righteous that He hurried to bring upon us the evil? No, this means, the Holy One, praised be He! did charity with Israel in that He caused the exile of Zedekiah to come while those of the exiled of Yechanyah were still alive; as it is said concerning Yechanyah (II Kings 24, 16) And the craftsmen and the locksmiths a thousand; i.e., Cheresh means if they opened a question all became deaf, and Massger (locker) if they closed the argument of a thing none could reopen it." And how many were they? A thousand. Ulla said: "The charity consists in that the Holy One, praised be He! made the exile earlier by two years indicated through the word V'noshantem." R. Acha b. Jacob said: "Infer from this that 'quick' means eight hundred and fifty-two years to the Omnipotent."