sharp knife. or, knife of flints. Before the use of iron was common, all the nations of the earth had their edge tools made of stones, flints, etc. Our ancestors had their arrows and spearheads made of flint; which are frequently turned up by the plough. And even when iron became more common, stone knives seem to have been preferred for making incisions in the human body. The Egyptians used such to open the bodies for embalming; and the tribe of Alnajab in Ethiopia, who follow the Mosaic institution, perform the rite of circumcision, according to Ludolf, cultris lapidibus, with knives made of stone.

circumcise

Genesis 17:10-14 This is my covenant, which you shall keep, between me and you and your seed after you; Every man child among you shall be circumcised...

Deuteronomy 10:16 Circumcise therefore the foreskin of your heart, and be no more stiff necked.

Deuteronomy 30:6 And the LORD your God will circumcise your heart, and the heart of your seed, to love the LORD your God with all your heart...

Romans 2:29 But he is a Jew, which is one inwardly; and circumcision is that of the heart, in the spirit, and not in the letter...

Romans 4:11 And he received the sign of circumcision, a seal of the righteousness of the faith which he had yet being uncircumcised...

Colossians 2:11 In whom also you are circumcised with the circumcision made without hands...