When the Lord asks Peter if he loves him, he is asking something he already knows. Yet he does not ask only once, but a second and third time. Each time Peter’s answer is the same: "You know I love you." Each time the Lord gives him the same command: "Tend my sheep."
Peter had denied Christ three times, and to counter this he must profess his faith three times. Otherwise his tongue would seem quicker to serve fear than love, and the threat of death would seem to have made him more eloquent than did the presence of life. If denying the shepherd was proof of fear, then the task of love is to tend his flock.
When those who are tending Christ’s flock wish that the sheep were theirs rather than his, they stand convicted of loving themselves, not Christ. And the Lord’s words are a repeated admonition to them and to all who, as Paul writes sadly, are seeking their own ends, not Christ’s.
"Do you love me? Tend my sheep." Surely this means: “If you love me, your thoughts must focus on taking care of my sheep, not taking care of yourself. You must tend them as mine, not as yours; seek in them my glory, not yours; my sovereign rights, not yours; my gain, not yours. Otherwise you will find yourself among those who belong to the ‘times of peril,’ those who are guilty of self-love and the other sins that go with that beginning of evils.”
So the shepherds of Christ’s flock must never indulge in self-love; if they do they will be tending the sheep not as Christ’s but as their own. And of all vices this is the one that the shepherds must guard against most earnestly; seeking their own purposes instead of Christ’s, furthering their own desires by means of those persons for whom Christ shed his blood.
The love of Christ ought to reach such a spiritual pitch in his shepherds that it overcomes the natural fear of death which makes us shrink from the thought of dying even though we desire to live with Christ. However distressful death may be, the strength of love ought to master the distress. I mean the love we have for Christ who, although he is our life, consented to suffer death for our sake.
Consider this: if death held little or no distress for us, the glory of martyrdom would be less. But if the Good Shepherd, who laid down his life for his sheep, has made so many of those same sheep martyrs and witnesses for him, then how much more ought Christ’s shepherds fight for the truth even to death and to shed their blood in opposing sin? After all, the Lord has entrusted them with tending his flock and with teaching and guiding his lambs.
With his passion for their example, Christ’s shepherds are most certainly bound to cling to the pattern of his suffering, since even the lambs have so often followed that pattern of the Chief Shepherd in whose one flock the shepherds themselves are lambs. For the Good Shepherd who suffered for all mankind has made all mankind his lambs, since in order to suffer for them all he made himself a lamb.
The strength of love ought to overcome the fear of death
From a treatise on John by Saint Augustine, bishop
The Liturgy of the Hours, Vol. 1, Office of Readings
Memorial of Saint Nicholas, Bishop (6 December)