Hebrews 10:28-31

Anyone who has ignored and set aside the Law of Moses is put to death without mercy on the testimony of two or three witnesses. [Deut 17:2-6] How much greater punishment do you think he will deserve who has rejected and trampled under foot the Son of God, and has considered unclean and common the blood of the covenant that sanctified him, and has insulted the Spirit of grace [who imparts the unmerited favor and blessing of God]? [Ex 24:8] For we know Him who said, “VENGEANCE IS MINE [retribution and the deliverance of justice rest with Me], I WILL REPAY [the wrongdoer].” And again, “THE LORD WILL JUDGE HIS PEOPLE.” [Deut 32:35, 36] It is a fearful and terrifying thing to fall into the hands of the living God [incurring His judgment and wrath].