The sign of God's covenant with Abraham was circumcision.
In the book of Genesis, God made a covenant with Abraham and promised to make him the father of many nations. As a sign of this covenant, God instructed Abraham to circumcise himself, his male children, and his male servants.
Circumcision is a surgical procedure that involves removing the foreskin of the penis. It was a common practice in the ancient Near East, but God gave it a new significance by making it the sign of His covenant with Abraham. Through circumcision, Abraham and his descendants were set apart as a people who belonged to God and were committed to following His ways.
The practice of circumcision continued throughout the Old Testament, and it was an important sign of Jewish identity and faith. In the New Testament, however, the Apostle Paul taught that circumcision was not necessary for salvation, and that faith in Jesus Christ was the true sign of belonging to God.
In summary, circumcision was the sign of God's covenant with Abraham, and it symbolized a commitment to follow God's ways and be set apart as His people.