The plan to forgive sins in Christianity was exposed from Old Testament , I believe BY GOD
: Jeremiah 31
"JER 31:31 Behold, the days come, says Yahweh
, that I will make a new covenant
with the house of Israel, and with the house of Judah:
JER 31:32 not according to the covenant that I made with their fathers in the day that I took them by the hand to bring them out of the land of Egypt; which my covenant they broke, although I was a husband to them, says Yahweh.
JER 31:33 But this is the covenant that I will make with the house of Israel after those days, says Yahweh: I will put my law in their inward parts, and in their heart will I write it; and I will be their God, and they shall be my people:
JER 31:34 and they shall teach no more every man his neighbor, and every man his brother, saying, Know Yahweh; for they shall all know me, from the least of them to the greatest of them, says Yahweh: for I will forgive their iniquity, and their sin will I remember no more."
So this was planned in advance. And this power was given to priests. I think this practice was from beginning of Church and I believe there are documents specifying conmfession for forgiveness of sins. That is was not labeled as sacrament, possible however I believe it was there since a way to forgive sins was planned by God, looks like from Old Testament.
So you have in Old Testament stonning to deathn for sins like abortion, fornication, maybe masturbation and such....that maybe did not solve much and confession that is more powerfull and angels were seen at confession erasing sins.
Again, to add insult to injury , in their confussion some Protestant groups went to stonning or blood atonement from confession that is to Old Law from New Law not knowing that Old Law may not offer salvation and entrance to heaven since it has not baptism.
" During his confession, St. Macarius saw a tablet that was all black representing the sins of St. Moses. An angel
was seen wiping off every sin as it was confessed by St. Moses, until finally the tablet was completely white."
Guys, have faith as I believe God told me that he is sending Holy Light every year to show that Eastern orthodox Church is true Church. Could it be true Church if it would teach you have sins saved while this was not the case? So as long as Holy Light comes to Eastern Orthodox Church, do not worry.
Confession erases sin of abortion too. Abortion, smoking, masturbation, fornication are erased through confesiion.