The Seven Last Words are:
- Father, forgive them; for they know not what they do. (Luke 23:34
- Amen I say to you, today you will be with me in paradise. (Luke 23:43)
- Eli, Eli, lama sabachthani? -- My God, my God, why hast thou forsaken me? (Matt 27:46)
- Father, into your hands I commend my Spirit. (Luke 23:46)
- Woman, behold your son; behold your Mother! (John 19:26-27)
- I thirst. (John 19:28)
- It is finished (John 19:30)
The first saying of Christ, as he is being crucified and mocked, having already withstood the mock trial that the High Priests and Sanhedrin held and the terrible scourging at the pillar, is "Father, forgive them; for they know not what they do." In these words we can begin to plumb the depth of the Mercy of Christ. After a night without sleep; having been abandoned by all but a very few of His closest friends, and having suffered terrible indignities, Christ prays for those who persecute Him -- as He has commanded us to do. In His complete surrender, he shows His greatest strength.
It is this strength that he gave to his disciples, as we see in the case of Saint Stephen, who not too long after will pray to Christ for mercy for those who are stoning him. The mercy of Christ -- the Divine Mercy, extend to all who avail themselves of it. The mercy of Christ is not limited to those things we do without knowing, but also to those things we do with full knowledge. Saint Faustina was shown a vision of an ocean, which represented the Divine Mercy; she was made to understand that her sins were but a drop in a bucket in comparison. It would be utter foolishness to think anything is beyond the mercy of Christ.
As long as the perons repents of sin and takes advantage of the Mercy of God, especially as found in the Sacrament of His Mercy, God is always faithful to forgive sinners.
This does have a moral dimension for us. As I mentioned, Saint Stephen prayed for those who were persecuting him. We are commanded by Christ to do the same. As we pray the Lord's Prayer, Forgive us our trespasses as we forgive those who trespass against us, we remember the words of Christ, "The same measure that you use will be used for you." As we pray for those who have harmed us, it becomes easier to forgive them. As we show mercy to those around us, we are assured that the same will be shown to us.