The Great Commentary of Cornelius a Lapide: S. John
And will go in and out . Will go out to the pastures, and after having fed will return to the resting-place, as sheep do. For the faithful will, when well fed, enter the fold of the Church, and again when hungry will go forth to the pastures of the soul, without any peril, for I will guide them to and fro. So Maldonatus.
But to go in and out signifies among the Hebrews to act with freedom, do one's own work, &c., and is connected with what follows. It means, the faithful man will move about everywhere without fear ; will do his duty, and whatever he does, whether at home or abroad, will everywhere find food for his soul. The phrase denotes security, confidence, and freedom of converse; and of doing everything, everywhere, for and through Christ. So Cyril, Chrysostom.
Symbolically and tropologically, S. Gregory ( Hom. xiv.) “ The faithful withdraws within himself by contemplation, and comes forth in action to do good works.” “ He will enter in,” says S. Augustine, “for inward meditation, he will go forth for outward action.” The author of De spiritu et anima, says, “ He will enter within to contemplate My Godhead, he will go forth to contemplate My Manhood, and in either case will find wondrous pastures.” And in another place S. Gregory writes, “ Within, they have the pastures of contemplation ; without, the pastures of good works ; inwardly they enrich their mind with devotions, outwardly they satiate themselves with good works.” And lastly, Theophylact says, “ He will enter in who has a care for the inward man ; he will go out who mortifies his members upon earth.”
Anagogically, Rupertus says, “He enters the Church by faith, to find therein pastures ; he will go out when at death he migrates therefrom into heaven.” “He enters,” says S. Augustine, “into the Church through the door of faith, and goes forth through the same door of living faith into eternal life, where he will find pasture.” And S. Gregory, “He will enter into faith, he will go forth to hope, and will find pasture in eternal satiety.”
Ver. 10. — The thief cometh not , &c. He shows what is the end and aim of him whom before He called a thief, and what on the contrary was His own. The thief and robber of the sheep, — as for instance a heretic or schismatic, a Scribe or Pharisee, or especially a false-Christ, — comes to carry off the sheep (i.e., the faithful) from God and the Church, whose property they are, to hand them over to the synagogue of Satan, and there kill them by heresy and sin, and cast them into hell. But I who am the true Shepherd of the sheep (i.e., of the faithful) came down from heaven, not for My own sake, but for that of the faithful, that being freed by Me, they may have the life of grace, even yet more abundantly. The word περισσόν may be taken either as an adverb (abundantly), or as an adjective (abundant), that is, surpassing, exceeding all measure, that is, that they may abound in My doctrine and grace, and may live thereby, quick in spirit, enriched with spiritual gifts both in this world by grace, and in the world to come by glory. So S. Cyril and others. Rupertus adds, “ that Christians may have more abundant grace than the Jews under the old law.” This abounding life of the spirit, inspired by Christ, you may see in S. Peter and the other Apostles, in Martyrs, Confessors, Virgins, &c. Hence the glowing language of S. Paul, “ Who shall separate us from the love of Christ,” &c. (Rom. viii.)
Ver. 11. — I am the good Shepherd, &c. I, the one only Prince of Shepherds, who will lay down My life for My sheep, to redeem them by My death from death, and confer on them both present and eternal life. Neither prophets, nor apostles, nor any one else could do this. For though they were slain for the sake of the faithful, yet they did not redeem them, sanctify, or beatify them. So Rupertus, Chrysostom, &c. S. Augustine adds that the prophets and apostles are counted as one and the same shepherd with Christ, as being under Him, sent also and guided and protected by Him. Christ therefore is that special and singular Pastor foretold by Ezekiel xxxiv. 23. (See notes in loc.)
Christ passes from the parable of the door to the more striking parable of the Shepherd . He is the door by which the sheep enter, and also the Shepherd of the sheep : that is not any ordinary one, but the chief, special, and Divine Shepherd. And He enters through the door, that is, by Himself and His own authority.
Besides this Christ rejoices in the title of Shepherd, as being most appropriate and most sweet. He used to be thus represented in very ancient pictures, at Rome, as carrying a sheep on His shoulders. Many of the patriarchs, who were types and ancestors of Christ, were shepherds, learning thereby (says Philo) to be shepherds of men, &c. “ If therefore thou wishest to know and to discharge the office of a true Pastor, see how a shepherd treats his sheep. Be so eminent in doctrine and sanctity among thy faithful ones, as to appear like a rational pastor among the irrational sheep, and as an angel among men ” (S. Chrysostom). He attends to his sheep one by one; let him lead them into richer pastures. He goes before them by his virtuous example, as S. Paul exhorts Titus (Tit. ii. 7). As a parish priest he drives away all heretics and hurtful persons. And let him feed his flock with sound doctrines and sacraments, and not fatten himself on the milk of his flock (Ezek. xxxiv. 2). Let him not be mercenary, seeking his own profit, paying court to the well-to-do and noble, and despising the rustics and mean of his flock. For Christ went about villages and towns, preaching the Gospel to the poor (Matt. xi.) Fisher, Bishop of Rochester, was a noble example of this ; he refused to exchange his poor bishoprick for a wealthier one, saying that he could render a better account at the day of judgment for his few sheep and small gains than he could for greater ones. For he said, “ If men did but know how exact an account would be required, they would not seek to obtain great and wealthy bishoprics ” (Sanders in Schism. Angl.) A good shepherd tenderly feeds and fosters the lambs and delicate ones of his flock (see Ezek. xxxiv. 4). And so does a parish priest and a bishop. (See the life of S. Abraham written by S. Ephrem.) He came from being an anchoret to be the pastor of a wild and barbarous people, and though cruelly entreated by them, he brought them by his indomitable patience, gentleness, and charity to submit to the laws of Christ.
Jacob, like a true shepherd, watched over his flock by day and night (Gen. xxxi. 40); and shepherds were watching over their flocks by night when Christ was born. So too should a parish priest or a bishop vigilantly watch over his flock, as his first duty. A shepherd risks his own life in guarding his sheep. So should a parish priest, when persecution or pestilence threatens ; as did SS. Athanasius, Chrysostom, Basil, Ambrose. Lastly, S. Peter, the chief pastor of the Church, lays down notes for the pastors under him (1 Pet. v. 2). See also S. Gregory (in Pastorali ), S. Bernard ( de Consider . ad Eugenium), and S. Augustine ( Tract de Pastoribus et Ovibus).
All these duties are summed up in charity, for charity supremely loves God, and for His sake the faithful committed to its care by God. (See also chap. xxi. 15.)
The good Shepherd layeth down his life for the sheep . This does not relate so much to the parable itself, as to that which is signified by it. For the natural Shepherd ought to count his own life of greater value than the lives of his sheep. And yet he ought to protect his sheep even at the risk of his life. But the shepherd of souls is bound, by his duty, to expose his bodily life to danger, for the spiritual life of the faithful committed to his charge. And hence he is bound to stand by them in the time of the plague, or provide some other qualified person to administer the sacraments to the sick, as did S. Charles Borromeo : and for this reason was canonised. And so also all the apostles, excepting S. John, suffered martyrdom for the sake of the faithful committed to their care. And so also nearly all the Roman Pontiffs down to S. Sylvester. But the leader of them all was Christ, who alone, as the best of Shepherds, laid down His life as a ransom, while all the others did so merely to manifest their faith, and as a pattern of virtue.