17 Over and above the laxity in the performance of Christian duties which is so widespread, We cannot but sorrow with you, Venerable Brothers, over the fact that very many churches, which during the War had been turned to profane uses, have not yet been restored to their original purpose as temples of prayer and of divine worship; moreover, that many seminaries whose existence is vital for the preparation and formation of worthy leaders and teachers of the religious life have not yet been reopened; that the ranks of the clergy in almost every country have been decimated, either because so many priests have died on the battlefield in the exercise of their sacred ministry or have been lost to the Church because they proved faithless to their holy vocation, due to the unfavorable conditions under which they were compelled to live for so long; and, finally, that in many places even the preaching of the Word of God, so necessary and so fruitful for "the edifying of the body of Christ" ( Ephesians iv, 12) has been silenced.
Source: Ubi Arcano Dei Consilio (Vatican.va)