'Sign of the Covenant' in the Bible

And God will say, This is a sign of the covenant which I give between me and between you, and between every breathing thing living which is with you for future generations.

And God will say to Noah, This the sign of the covenant which I established between me and between all flesh which is upon the earth.

And ye circumcised the flesh of your uncircumcision; and it was for a sign of the covenant between me and between you.