Genesis 17:11-14

11You shall be circumcised in the flesh of your foreskins, and it shall be a asign of the covenant between me and you. 12He who is beight days old among you shall be circumcised. Every male throughout your generations, whether born in your house or cbought with your money from any foreigner who is not of your offspring, 13both he who is born in your house and he who is bought with your money, shall surely be circumcised. So shall my covenant be in your flesh an everlasting covenant. 14Any uncircumcised male who is not circumcised in the flesh of his foreskin shall be cut off from his people; he has broken my covenant.”

Joshua 5:3

3So Joshua made flint knives and circumcised the sons of Israel at Gibeath-haaraloth.
 Gibeath-haaraloth means the hill of the foreskins

1 Samuel 17:26

26And David said to the men who stood by him, “What shall be done for the man who kills this Philistine and takes away ethe reproach from Israel? For who is this funcircumcised Philistine, that he should gdefy the armies of hthe living God?”

1 Samuel 17:36

36Your servant has struck down both lions and bears, and this uncircumcised Philistine shall be like one of them, ifor he has defied the armies of the living God.”
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