Those excommunicated are not to partake in the Lord's supper. However, upon repentance, the person is welcomed back into fellowship within the body of Christ. The cancellation of sin. Expiation and propitiation are similar but expiation does not carry the implication of dealing with wrath, of appeasing it through a sacrifice. Generally speaking, propitiation cancels sin and deals with God's wrath.
Expiation is simply the cancellation of sin.
It is synonymous with trust. He is a person who will manifest himself near the culmination of this epoch shortly before the physical return of Christ. Jesus warned about false prophets in Matt. False prophets teach false doctrine and lead people away from the true gospel message and teaching of God found in the Bible. Each of them distorts the truth sufficient to cause damantion.