Quran &Sunnah

Those who believe and work righteous deeds from them shall We blot out all evil (that may be) in them and We shall reward them according to the best of their deeds. (29:7)

In striving to purify our Faith and our Life, we are enabled to avoid the consequences of our misdeeds for Allah will forgive any evil in our past, and help to the attainment of a Future based on the best of what we have done rather than on the poor average of our own merits. The atonement or expiation is by Allah's Mercy, not by our merits or the merits or sacrifice of anyone else.