FAQ: Isn't Judaism equally as useful as Christianity for sinners seeking God's
forgiveness? Isn't that the whole purpose of Yom Kippur, a.k.a. the Day of
Atonement?
That would be a gross oversimplification. God gave us Yom Kippur because it is helpful. But the key to forgiveness is repentance. The difference between the righteous man and the wicked man is that the righteous man repents, and the wicked man does not. Proverbs 24:16 For a righteous man falleth seven times, and riseth up again, But the wicked stumble under adversity.
Let's look for a moment at the story of David and the prophet Nathan. David had committed adultery with Bathsheba, and then had sent her husband Uriah to his death so that he could marry her. The prophet Nathan goes to David, and uses an allegory to reveal to David the depth of his sin. David's heart is moved, and he exclaims "I have sinned against the LORD."
Now what does Nathan then say to David? Quick, go offer a sin sacrifice so that you can be forgiven? No, he doesn't say that. Does he say, Well God will forgive you on Yom Kippur? No, he doesn't say that either. Instead he says to David, "The LORD has taken away your sin." So God forgave David without any sacrifice at all, based solely on his repentance.
The sacrificial system is meant to be a help, not a hindrance. Psychologically, human beings do better if we have concrete steps we can take to deal with facing our flaws, and being restored to the good graces of God. In the case of Yom Kippur, it is a day specifically set aside for us to deal with God regarding the sins of Israel. While we do personally introspect on Yom Kippur, its key is the communal connection -- going to God not as an individual but as a People. All the various prayers of repentance are said in the plural, we, not the singular, I. By facing our sins on Yom Kippur as a collective, rather than individuals, it strengthens the Jewish people.
Sorry for the length of the post -- I personally hate long posts. But it was necessary because I needed to address two things: repentance (not sacrifice) being the heart of forgiveness, and the purpose of Yom Kippur.