Source: H. Graetz, History of the Jews, volume II (Philadelphia: Jewish Publication Society of America, 1893) 473.
"[According to the Mishna, t]he discharge of certain duties secures the enjoyment of reward on earth and in the world to come; such are the veneration of parents, charity, timely attendance at the school, hospitality, and endowment of (indigent) brides, the accompanying of corpses to the grave, devout prayer, peace-making, and especially the pursuit of religious studies (Talmud Torah)...The most heinous and atrocious sins are expiated by death, and lesser ones by repentance and the Day of Atonement, while pardon was obtained for sins of negligence by sacrifice."
What must one do to be saved--to be forgiven of sins, to receive acceptance from God, and to enter the good afterlife? Many Christians believe that this is the crucial issue that separates Christianity from Judaism and Islam. For them, Christians hold fast to justification by faith through grace alone, whereas other religions embrace some form of salvation by works. At a Jewish institution, a colleague of mine wrote a paper that contrasted the Mishnah with Tertullian, and he argued that Christians are grace-centered, whereas Jews focus more on the nuts-and-bolts of halakah.
To my surprise, the student's professor responded that Tertullian was actually quite legalistic. This somewhat undermined my colleagues stereotype of Christianity, but I can actually see the professor's point as I read through Christian literature. Look at all the good deeds in Graetz's quote that the Mishnah treats as a path to eternal life. A Christian wouldn't agree with that sort of "salvation by works" mindset, would he?
Not so fast! Barnabas 14:20 says, "Thou shalt also labour with thy hands to give to the poor, that thy sins may be forgiven thee."
(This is according to the translation in The Lost Books of the Bible and the Forgotten Books of Eden. The version on BibleWorks does not have that. It numbers the chapters and the verses differently, and it has, "Thou shalt remember the day of judgment, night and day. Thou shalt seek out every day the faces of the saints, either by word examining them, and going to exhort them, and meditating how to save a soul by the word, or by thy hands thou shalt labor for the redemption of thy sins." So I don't know if there are different manuscripts at work, or what.)
II Clement 16:4 (in the BibleWorks version) says that almsgiving lessens the burden of sin. These Christian writings are consistent with the deutero-canonical documents, which state that giving alms performs an atoning function (Sirach 3:30; Tobit 12:9). And, to the Protestants who will say, "That's one reason we don't like the apocrypha--it promotes salvation by works," take a look at what Daniel tells Nebuchadnezzar in Daniel 4:27: "atone for your sins with righteousness, and your iniquities with mercy to the oppressed, so that your prosperity may be prolonged" (NRSV). I do believe that Daniel is part of the Protestant canon.
Something else to note is that Origen, like the Mishnah, believed that a person's death could atone for his sins (or at least certain ones). I remember reading this in Origen's Homilies on Leviticus.
Don't get me wrong. The early Christians and the church fathers firmly believed that Christ atoned for people's sins, and they held fast to the necessity of faith in Jesus Christ for salvation. In terms of atonement, they wouldn't view almsgiving as an alternative to Jesus Christ.
But they saw atonement differently from a lot of contemporary evangelicals. For the ancient Christians, people needed forgiveness even after they embraced Jesus Christ at baptism.