Atonement of Sins

Since all mankind are held to be sinners because of original sin, Christian doctrine holds that an atonement is required to be forgiven by God the Father — following the Old Testament practice of the Jews, which required an offering for forgiveness.

Blood sacrifice

Blood sacrifice is presented as required for forgiveness in the Old Testament:

כִּ֣י נֶ֣פֶשׁ הַבָּשָׂר֮ בַּדָּ֣ם הִוא֒ וַאֲנִ֞י נְתַתִּ֤יו לָכֶם֙ עַל־הַמִּזְבֵּ֔חַ לְכַפֵּ֖ר עַל־נַפְשֹׁתֵיכֶ֑ם

“For the life of the flesh is in the blood; and I have given it to you for making atonement for your lives on the altar; for, as life, it is the blood that makes atonement.”

A worthy offering, in this account, must itself be sinless — and since all human beings are held to be sinners, only Jesus (peace be upon him) could satisfy that requirement, being sinless. This is the core teaching of Paul, who wrote much of the New Testament. In his letter to the Romans, for example:

τὰ γὰρ ὀψώνια τῆς ἁμαρτίας θάνατος, τὸ δὲ χάρισμα τοῦ θεοῦ ζωὴ αἰώνιος ἐν χριστῶ ἰησοῦ τῶ κυρίῳ ἡμῶν.

“For the wages of sin is death, but the free gift of God is eternal life in Christ Jesus our Lord.”

For a Muslim response to whether human sacrifice is actually necessary for forgiveness, according to the Old Testament’s own words, see Sin in Christian Thought. For a detailed question-and-answer treatment of this topic, see Atonement of Sins: Questions & Answers.