God give us the dignity of being “causes” (and we are sons in the Son!). We are given the dignity of proclaiming the Gospel, of caring for the sick and needed and yes of praying for and sacrificing for others salvation…We are given that dignity of being “causes” (by grace etc) in the good of others and of the world…
Such does not mean that the sacrifice on the Cross was not enough! It was superabundant to say the least.
But as Paul noted:
“Now I rejoice in my sufferings for your sake, and in my flesh I complete what is lacking in Christ’s afflictions for the sake of his body, that is, the church…” (Colossians 1.24- RSV CE)*
Now does that mean that there is something lacking in the sufferings of Christ?
The rather were super abundant.
As one of my Professors at Fran. Un. Steubenville put it (either Dr. Martin or Dr. Hahn) - what is lacking? Our sufferings.
Our Sufferings - joined with his in his pascal mystery. Not that they are needed - as if his sufferings were not “enough” (He could have saved us without such even!).
Rather He makes a space as it were for us - for our love to be involved.
We are as I noted given the dignity of cooperating - of being a kind of (secondary) cause in good and even yes the salvation of others.
Prayer etc is a reality in the universe. Just as giving a cup of cold water to a thirsty person is a reality.
*
ewtn.com/devotionals/biblesearch.asp