Peter's question probably came in response to Jesus' teaching about restoring repentant sinners to fellowship with God and others (Matthew 18:15-19). Jesus had advocated honest but loving confrontation of sinful behaviour, encouraging repentance and leading to reconciliation. Peter got the message but asked what should be done with persistent offenders.
 
The rabbis of his day taught that forgiveness should be offered on three occasions. Peter sensed that Jesus might be more generous and asked if the limit of three offences might be extended to seven times (seven was considered to be the number of perfection or completeness). The Lord multiplied that number by itself. He was saying that there is no limit to forgiveness in God's economy: no limit to the times that repentance must be met with love and reconciliation.
 
Peter's question seems to presume that he would always be right and it would always be the fault of others which would be the problem! He would soon learn that Jesus was willing to forgive his denial. God's love is very generous indeed. Without that, there would be no gospel of grace. Yet it is surprising how many people cower in their sins and try to hide from God, even though He longs for them to rejoice in His forgiveness.
 
God is not vengeful towards people who are repentant. He keeps on loving them, drawing them back into relationship with Himself. The church needs to learn to do the same. Repentance must always be met by forgiveness and reconciliation. Of course there would be plenty of sinners who do not believe they are in the wrong: they cannot enjoy the grace of forgiveness. But those who are truly sorry for their sins need to know that Father God wants to restore them; and the church must also.