Everlasting covenant between God and us

Genesis 17:9-14
God made a covenant with Abraham and his descendants.
The sign of the covenant between God and Abraham
Every male in his house must be circumcised, including those born in his household or bought with money from foreigner.
The covenant in their flesh is to be an everlasting covenant.
The physical sign of circumcision gathers not only Abraham but also Ishmael and the whole multi-racial household into the covenant.
Why?
God made a physical sign as covenant between God and Abraham, his descendants.
Covenant be kept needs shed blood. Jesus Christ shed for us and made a new covenant between God and us.
How?
Our sign of Salvation is the Cross of Jesus and his blood.