God is so serious about covenant that he almost killed Moses for not circumcising his son (sign of the Abrahamic Covenant) and God told Joshua to circumcise the 2nd generation (out of wilderness, 20 years old and upward) before going in to take the Promised Land. Abraham was declared righteous before he was circumcised (sign of the Abrahamic Covenant). We Believers are partakers of the New Covenant as well as the everlasting Abrahamic Covenant as we are "those who are of faith", yet we are not required to circumcise our sons.
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