How does that relate to what Jesus said in Luke 17? Are you implying that when Jesus said IF they repent then forgive them...that we just ignore what Jesus said?
Further consideration reveals to me that you are making a logical mistake.
"If he repents, then forgive him" makes "if he repents" a
sufficient condition for forgiveness, not a
necesary condition. The mere presence of penance is sufficient in order for us to forgive the penitent. Christ commands me that, if my brother does penance, then in no circumstances should I not forgive him. There is no case in which my brother should do penance and I not forgive him.
Christ didn't say "forgive him only if he repents" in the sense of establishing penance as a necessary condition of forgiveness. If he did, then it certainly would not have made any sense for St. Paul to write what he wrote, namely, that Christ died for us even when we were still sinners. By His own standard, had Christ made penance a necessary condition for being forgiven, then neither could he have died for us nor could He have called out to the Father on behalf of the unrepetent Jews who were crucifying him: "Forgive them, they know not what they are doing!"