Aquinas on the "efficacy" of the Passion

We've been walking our way through the Passion Account according to St. Mark in our midweek Lenten services this year. We have walked with Jesus through the night of His anointing beforehand for burial by Mary (Mark 14:1-11)... we sat down with Jesus to celebrate with Him His final passover (Mark 14:12-31)... we prayed with Jesus in the garden of Gethsemane (Mark 14:32-52)... we witnessed the false charges and the verdict of blasphemy be laid against Jesus (Mark 1453-63)... last night we read of Peter's denial of Christ and faced the truth of own denial of our faith in Christ (Mark 66-72).

"Jesus, grant that balm and healing in Your holy wounds I find. Every hour that I am feeling pains of body and of mind, should some evil thought within tempt my treacherous heart to sin- show the peril, and from sinning, keep me from its first beginning" (LSB 421:1).

With all this background in mind, I picked up my Treasury of Daily Prayer this morning and what do I find? An interesting writing from Thomas Aquinas (A+D 1225-1274) in which he responds to arguments that the Passion of Christ has no worth for us Christians. It's interesting, because if the Passion of Christ Jesus has no "efficacy" for us Christians in this day and age, what would be the worth of meditating upon it? Just for purely historical value? If so, I think we could find better things to do with our time! Read what Aquinas has to say:

The argument against the power of Christ's Passion: the devil exercises his power over men by tempting them and molesting their bodies. But even after the Passion he continues to do the same to men. Therefore we are not delivered from his power through Christ's Passion.

Aquinas responds: God permits the devil to tempt men's souls and harass their bodies, yet there is a remedy provided for humanity through Christ's Passion, whereby a person can safeguard himself against the enemy's assaults, so as not to be dragged down into the destruction of everlasting death. And all who resisted the devil previous to the Passion [in Old Testament times] were enabled to do so through faith in the Passion, although it was not yet accomplished.

A further argument is put forth: according to Hebrews 10:14 ["For by a single offering He has perfected for all time those who are being sanctified"], the might of Christ's Passion endures forever. But deliverance from the devil's power is not found everywhere, since there are still idolaters in many regions of the world; nor will it endure forever, because in the time of Antichrist he will be especially active in using his power to the hurt of men, because it is said of him (2 Thess. 2:9[-10]): "The coming of the lawless one is by the activity of Satan with all power and false signs and wonders, and with all wicked deception." Consequently it seems that Christ's Passion does not deliver the human race from the power of the devil.

Aquinas responds: God permits the devil to deceive men by certain persons, and in times and places, according to the hidden motive of His judgments. Still, there is always a remedy provided through Christ's Passion for defending themselves against the wicked snares of the demons, even in Antichrist's time. But if any man neglect to make use of this remedy, it detracts nothing from the efficacy of Christ's Passion. 

source: Treasury of Daily Prayer, St. Louis: Concordia Publishing House, 2008, pp.124-5.