... R. Yochanan said: The voice is the voice of Jacob (Gen. XXVII, 22)--the voice [of distress caused by] the Emperor Hadrian, who slew eighty thousand myriads of human beings at Beitar (the final battle site of Bar Kochba and his troops).
Eighty thousand vanguard troops besieged Beitar where Bar Koziva was located who had with him two hundred thousand men with an amputated finger [Bar Kochba required rabbinical students that wanted to fight in his army to sever a finger as proof of bravery].
... For three and a half years the Emperor Hadrian surrounded Beitar. In the city was R. Eleazar of Modi'im who continually wore sackcloth and fasted, and he used to pray daily, Lord of the Universe, sit not in judgment to-day!' so that [Hadrian] thought of returning home. ...
They slew the inhabitants until the horses waded in blood up to their nostrils, and the blood rolled along stones of the size of forty se'ah (71 gallons....) and flowed into the sea [staining it for] a distance of four miles.
Should you say that [Beitar] is close to the sea; was it not in fact four miles distant from it?
Now Hadrian possessed a large vineyard eighteen miles square, as far as from Tiberias to Sepphoris, and they surrounded it with a fence consisting of the slain at Beitar. Nor was it decreed that they should be buried until a certain king arose and ordered their interment. Tiberias in 1862, the ruins reminiscent of its ancient heritage. ...
Tzippori, also known by several other names & spellings including Sepphoris, is one of the oldest Jewish settlements to be uncovered by archaeologists, and one of the richest in what has been found there. ...
R. Huna said: On the day when the slain of Beitar were allowed burial, the benediction 'Who are kind and deals kindly' was instituted [and included in the "Birkat Hamazon" blessings said after a meal] Birkat Hamazon (×ר×ת ×××××), known in English as the Grace After Meals (lit. ...
'Who are kind' because the bodies did not putrefy, and 'deals kindly' because they were allowed burial.
R. Yochanan said: The brains of three hundred children [were dashed] upon one stone, and three hundred baskets of capsules of tefillin (phylacteries) were found in Beitar, each basket being of the capacity of three se'ah, so that there was a total of three hundred se'ah. Tefillin (Hebrew: תפ×××), also called phylacteries, are either of two boxes containing Biblical verses and black, leather straps attached to them which are used in orthodox Jewish prayer. ...
R. Gamliel said: There were five hundred schools in Beitar, and the smallest of them had not less than three hundred children.
They used to say, If the enemy comes against us, with these styluses we will go out and stab them!'
When, however, [the people's] sins did cause the enemy to come, they enwrapped each pupil in his book and burned him, so that I alone was left.
He applied to himself the verse, My eye affected my soul, because of all the daughters [i.e. inhabitants] of my city."
Babylonian Talmud, Gittin 57-58
[In explanation of the verse]"He hath cut off in fierce anger all the horn of Israel."[3] Rabbi Zera said in the name of rabbi Abbahu, who quoted rabbi Johanan: 'These are the eighty thousand battle trumpets which assembled in the city of Bethar when it was taken and men, women and children were slain until their blood run into the Great Sea [a Hebrew term for the Mediterranean].
It has been taught that rabbi Eleazar the Great said: 'There are two streams in the valley of Yadaim, one running in one direction and one in another, and the Sages estimated that at that time they ran with two parts of water to one of blood.'[4]
In a Baraitha [5] it has been taught: 'For seven years [after the massacre at Beitar] the gentiles [Roman settlers in the land Hadrian then named Palestina] fertilized their vineyards with the blood of Israel without using manure.' A baraitha is an external piece of Jewish oral law, usually from the same era as the Mishnah and often by the same sages. ...