Tunnels and Enemies of the Jews

Are the Gaza tunnels new?

Not really.

From the Babylonian Talmud Tractate Berachot 54:

Our Rabbis taught: If one sees the place of the crossing of the Red Sea, or the fords of the Jordan, or the fords of the streams of Arnon...for all of these he should give thanksgiving and praise to the Almighty...whence is the title derived for the fords of the streams of Arnon? — Because it is written: Wherefore it is said in the book of the Wars of the Lord, Eth and Heb in the rear; [in explanation of which] a Tanna taught: 'Eth and Heb in the rear' were two lepers who followed in the rear of the camp of Israel, and when the Israelites were about to pass through [the valley of Arnon] the Amorites came and made cavities [in the rocks] and hid in them, saying, When Israel pass by here we will kill them. They did not know, however, that the Ark was advancing in front of Israel and leveling the hills before them. When the Ark arrived there, the mountains closed together and killed them, and their blood flowed down to the streams of Arnon. When Eth and Heb came they saw the blood issuing from between the rocks  and they went and told the Israelites, who thereupon broke out into song. And so it is written, And he poured forth the streams2  [from the mountain] which inclined toward the seat of Ar  and leaned upon the border of Moab.

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