Christ said, “The hireling fleeth, because he is an hireling, and careth not for the sheep” (Jn 10:13). If the Apostles were shepherds, not hirelings, why did they flee when persecuted? Moreover, why did Christ give them the instruction: “When they persecute you in this city, flee ye into another” (Mt 10:23)? St. Augustine addresses this in the following comments, gathered from his writings:
He explains: “A servant of Christ, and minister of His Word and Sacraments, may flee from city to city, when he is specially aimed at by the persecutors, apart from his brethren; so that his flight does not leave the Church destitute. But when all, that is, Bishops, Clerics, and Laics, are in danger in common, let not those who need assistance be deserted by those who should give it. Let all flee together if they can, to some place of security; but, if any are obliged to stay, let them not be forsaken by those who are bound to minister to their spiritual wants. Then, under pressing persecution, may Christ’s ministers flee from the place where they are, when none of Christ’s people remain to be ministered to, or when that ministry may be fulfilled by others who have not the same cause for flight. But when the people stay, and the ministers flee, and the ministry ceases, what is this but a damnable flight of hirelings, who care not for the sheep?”
Elsewhere, he advises: “We must love the shepherd, beware of the wolf, tolerate the hireling. For the hireling is useful so long as he sees not the wolf, the thief, and the robber. When he sees them, he flees.”
This should come as no surprise. St. Augustine points out: ”He would not be an hireling, did he not receive wages from the hirer. Sons wait patiently for the eternal inheritance of their father; the hireling looks eagerly for the temporal wages from his hirer; and yet the tongues of both speak abroad the glory of Christ. The hireling hurteth, in that he doeth wrong, not in that he speaketh right: the grape bunch hangeth amid thorns; pluck the grape, avoid the thorn. Many that seek temporal advantages in the Church, preach Christ, and through them Christ’s voice is heard; and the sheep follow not the hireling, but the voice of the Shepherd heard through the hireling.”
Quotations from St. Thomas Aquinas, Catena Aurea: Commentary on the Four Gospels Collected Out of the Works of the Fathers, Vol. IV, Part I (Oxford: John Henry Parker, 1845).