11 But they did not preach chastely, concerning whom the Apostle sighs. But what does he say? “What then? Notwithstanding every way, whether by occasion or in truth, Christ is preached.” He suffers then that hirelings there should be. The shepherd preaches Christ in truth, the hireling by occasion preaches Christ, seeking something else. Notwithstanding, both the one and the other preaches Christ. Hear the voice of the shepherd Paul; “Whether by occasion or in truth, Christ is preached.”
Himself a shepherd, he was pleased to have the hireling. For they act where they are able, they are useful as far as they are able. But when the Apostle for other uses sought for those whose ways the weak ones might imitate; he says, “I have sent unto you Timotheus, who shall bring you into remembrance of my ways.” And what does he say? “I have sent unto you a shepherd, to bring you into remembrance of my ways;” that is, who himself also walks as I walk. And in sending this shepherd, what does he say?
“For I have no one so likeminded, who with sincere affection is anxious for you.” Were there not many with him? But what follows? “For all seek their own, not the things which are Jesus Christ's;” that is, “I have wished to send unto you a shepherd; for there are many hirelings; but it were not meet for an hireling to be sent.” An hireling is sent for the transaction of other affairs and business; but for those which Paul then desired, a shepherd was necessary. And he scarcely found one shepherd among many hirelings; for the shepherds are few, the hirelings many.
But what is said of the hirelings? “Verily I say unto you, they have received their reward.” Of the shepherd, what says the Apostle? “But whosoever shall cleanse himself from such as these shall be a vessel unto honour, sanctified, and useful to the Lord, prepared always unto every good work.” Not unto certain things prepared, and unto certain not prepared, but “unto every good work prepared.” So much have I said, concerning the shepherds.
Source: Sermons on Selected Lessons of the New Testament (New Advent)