Then came Peter to him, and said, Lord, how oft shall my brother sin against me, and I forgive him? till seven times? Jesus saith unto him, I say not unto thee, Until seven times: but, Until seventy times seven. Matthew 18:21-22
"The Jewish Rabbis at that time taught that a man was to be forgiven three times, but no more. Peter multiplied this number by two, added one more for good measure, and then patted himself on the back and said, "Look what a wonderful fellow I am to be willing to forgive like that!" Peter indeed was willing to forgive, but his mistake was that he measured himself by a human rather than a divine standard.
So Jesus says to him, "Not just seven times, Peter, should you forgive your brother, but seventy times seven." An alternative in translation is "seventy-seven times" instead of "seventy times seven." At any rate the meaning is the same, for Jesus was teaching that a person should always be ready to forgive. It is not a problem of counting but a problem of conduct."
(Lightfoot, Neil R. 1986. The Parables of Jesus. Vol. 1 (Revised). Abilene, TX: A.C.U. Press., pg 47)