What is the burden of the offended?
1. They were hurt, sinned against, betrayed…a heavy burden indeed
2. They must confront the offender, in love, seeking reconciliation…a burden the world believes better avoided (though the world encourages telling everybody else but the offender)
3. They must forgive the repentant offender…a burden improbable to bear
4. They must ask for forgiveness, from the offender, where they have sinned in response to being sinned against…a burden IMPOSSIBLE to bear in one’s own strength
Jesus teaches to the second and third points (above) directly in Luke 17:1-19.
Indeed, Jesus knew the idea of forgiving a deep wound would be met with resistance so he begins the teaching with three warnings:
1. “Woe” to the unforgiving (17:1)
2. It would be better for the unforgiving to hang “a millstone around his neck” and be “cast into the sea” (17:2)
3. The one tempted to not forgive must “pay attention” (17:3)
At the request of Jesus to forgive someone who sins against them seven times in a day (vs. 4), the apostles cry foul and cry for more faith (vs. 5).
Now please note this…instead of commiserating, Jesus challenges the ones offended.  Mark that, Jesus is not content to allow the one SINNED AGAINST to avoid the command to forgive.  Jesus is either incredibly calloused OR He is wanting something better for the apostles than the paltry satisfaction of nursing an offense.
Thus, Jesus gives the apostles three thoughts to ponder.  Three parables that will show the apostles that though they cried for more faith (a matter of quantity), what they needed was the right KIND of faith (a matter of quality).
The right kind of faith can…
1. Move trees (hyperbole to make point; vs. 6)
2. Obey even when it hurts; can perform its duty as delight despite burden (vss. 7-10)
3. Will, out of praise for God has done, do the impossible (vss. 11-19)
It was inconceivable that a Samaritan would ever fall at the feet of a Jew in worship…unless the Samaritan was eternally grateful.  The kind of faith that forgives is like (vs. 6), not the begrudging servant (vss. 7-9), but like the healed leper (vss. 11-19).
It is IMPOSSIBLE to believe that God would require of us forgiveness…but this is exactly what He requires AND demonstrated.  Indeed, God would seem to infer that the refusal to forgive is worse the repented of original offense.
I trust you recall that Jesus washed the feces off of the feet of Judas before the betrayal…knowing full well the betrayal was coming.  If you would know this kind of love; if this kind of love has set you free then go wash the feet of your betrayer and forgive when/if they repent.
If you know AND would know more of what your Savior did for you in going to the cross, obeying His Father despite the pain with joy (Heb 12:1-2), and forgiving you in advance for what you would do…then forgive those who have hurt you and repented.
10,000 Blessings in the Forgiver,
Jim