Soul of the Apostolate.
Chautard, Dom Jean-Baptiste (1977-06-01).
TAN Books. Kindle Edition.
"The mortal life of Our Lord was nothing else but a continual manifestation of this inexhaustible liberality. The Gospel shows us the Redeemer scattering along His way the treasures of love of a Heart eager to draw all men to truth and to life. This apostolic flame has been passed on by Jesus to His Church, which is the gift of His love, which diffuses His life, manifests His truth, and shines with the splendor of His sanctity." (p. 5)
This 1946 title is a veritable classic, which formed part of the library of most priests with 60 years of ministry under their belts. Except for the above quote, it can be hard reading because it comes out of a world and a vocabulary unfamiliar to most folks. Nonetheless, it makes an important point that would be worth the while of lots of pastoral agents of today to learn. The soul of the apostolate is the interior life, the ongoing and tenacious quest for sanctity, for union with Christ.
Apart from insisting that the personal sanctity of the priest is the key to spiritual fruitfulness, Chautard spends time debunking the claim that the success of the then popular Catholic Action Movement rested on gimmicks. He in effect restores the heart to St. John Bosco's oratory movement: more than soccer, Foosball, marching bands and clean movies, he insists that promoting the few young men and boys capable of interiority, giving them spiritual direction through weekly confession, that there is no other way to spread the Gospel.
I read the book on my retreat this summer and recommend it highly. It is a Catholic alternative to much of what is presently in favor among those zealous folk who are truly seeking the spread of the Kingdom. I really think that it presents some of the key elements for the recovery and promotion of the faith among the younger generation. It is far more concrete about the requirements of a genuine priestly spirituality, yes also for our day, than most of what you will find on the market.