Eventually, he put his daughter’s soul on the paten at Holy Mass, next to the Sacred Host. He entrusted her to Christ every day at Mass so that she would discover the truth. After five months of this eucharistic prayer, his daughter said: “You were right, Dad. He’s not good for me. I broke up with him.”

Such is the power of what the Church calls co-redemption. My friend connected his petition for his daughter with Christ’s all-powerful redemptive work in the Eucharist. With faith, persistence and, above all, Christ’s sacramental grace, he reclaimed his daughter from a very dangerous situation.

Another kind of co-redemption is not so clear or satisfying but is just as valid. A bank employee expressed concern that the bank was heavily invested in pharmaceutical companies that manufactured abortifacient drugs, but her bosses told her to follow the bank’s policy and not to spread discontent. Ultimately, she resigned and took a lower-paying job at another bank.

By resigning rather than doing immoral work, the woman was a co-redeemer. She was uniting herself with Christ’s sacrifice and plan of redemption for the world, which includes honesty and justice in the workplace.

The word redemption is derived from the Latin redemo, which literally means to “buy back something.” Christ did this with His life on earth: He bought back the human race from the slavery of sin and despair.

Catholic theology teaches that redemption is the work of the three Divine Persons — Father, Son and Holy Spirit. God the Father sent God the Son to redeem us, and both sent God the Holy Spirit to sanctify us. Each Person is therefore involved in loving us and saving us, though only the Second Person became a man, lived a human life, and died on the cross.

Such is the real reason for the effectiveness of Christ’s life and sacrifice: As an infinite Person, only He could give equal reparation to the two Infinite Persons offended by sin, who are also God. Only an Infinite Person with a divine nature can truly make atonement to an infinite God.

At the same time, as a human being like you and me, Christ can offer that reparation for us, who are the ones offending. He experienced hunger, thirst, cold, pain and sadness, just as we can — but in a more intense way. Unlike us, He was a Divine Person who had a perfect human nature, and therefore He could never commit a sin. Yet out of love for us, and to redeem us (to “buy us back”), He took upon Himself our sins, and paid the full price for them in His soul and flesh. In St. Paul’s graphic words, He became sin for our sakes, so that we might be freed from sin (2 Corinthians 5:21).

It’s hard to understand such a complete, wild love. To offer oneself as a substitute for punishment when another is guilty of a grave crime — this is truly extraordinary.

Christ’s redeeming work allows us to redeem the world with Him. Such is the meaning of co-redemption. We, too, are human beings who can feel hunger, pain, cold and disappointment. By connecting these human experiences with Christ the Redeemer, we can truly be His eyes, arms and hands in the world.

Father Giesler is a priest of Opus Dei living at the Wespine Center in St. Louis. He has written a book and several articles on Sacred Scripture and the natural law.