Redemptive Suffering and Colossians 1:24

Last evening I was listening to an old friend telling her missionary stories from the past 6 years and how she felt totally spent and needed an extended time to heal. All I could think of (to encourage her) was a scripture passage in Colossians 1:24:

" I am now rejoicing in my sufferings for your sake, and in my flesh I am completing what is lacking in Christ’s afflictions for the sake of his body, that is, the church."

I didn't say it to her. I was worrying that I myself didn't understand the concept of "Redemptive Suffering", or the concept of "Offering it up" our suffering; and in fact, the understanding of Col 1:24 itself. So I decided to look it up.

First I tried to google "Col 1:24 commentary". The results were mostly from the protestant sources - none of them really explains the concept of Redemptive Suffering at all. I realized that the concept of Redemptive Suffering was really something I learned since becoming a Catholic. So I tried "col 1:24 to offer it up your suffering" and found this very helpful and recent article by Father Thomas Berg in the Catholic Digest: "What does it really mean to ‘offer it up’?":

(1) The Catechism of the Catholic Church (CCC #618) gives us the theological framework of the practice of “offering it up”: "Christ makes us — members of his Mystical Body — participants in that redemptive self-offering of Christ our head". This is the mystery of the redemptive suffering that Paul describes in Col 1:24.

(2) In his encyclical (Salvifici Doloris, 19) Pope St. John Paul II described the relationship between Christ’s redemptive sacrifice and our mysterious participation in it with these words:

"In bringing about the Redemption through suffering, Christ has also raised human suffering to the level of the Redemption. Thus each man, in his suffering, can also become a sharer in the redemptive suffering of Christ."

(3) Our Blessed Mother in most of her apparitions, particularly at Fatima "... has repeatedly reminded us of this mysterious participation in redemptive suffering. The three visionaries of Fatima received her message as a call, in part, to live the rest of their lives finding frequent opportunities to offer acts of reparation for sinners."

(4) The Daily Offering prayer (which I pray every day) "captures what should be ideally our habitual attitude of offering the “prayers, works, joys, and sufferings of this day in union with the holy sacrifice of the Mass throughout the world.” To live with that attitude is something beautiful in God’s eyes."..."A readiness to offer up sacrifices is the best antidote to a mentality of complaining, irritability, negativity, and cynicism."