Why is Jesus called “the Good Shepherd”?

The human soul cries out, “Tell me, O you whom I love, where you feed your flock, where you make it rest at noon. For why should I be as one who veils herself by the flocks of your companions?” (Song 1:7). St. Gregory of Nyssa says, “Where do you pasture your flock, O Good Shepherd, you who carry the whole flock on your shoulders? For the whole human race is one herd, which you have taken on your shoulders. Show me the place where there is new-grown grass, make known to me the water of repose (cf. Ps. 23:2), lead me out to the nourishing pasture, call me by name in order that I, I your sheep, may hear your voice, and by your voice give me eternal life.”⁷⁵⁵

And St. Clement of Alexandria says, “Feed us, the children, as sheep. Yes, Master, fill us with righteousness, Your own pasture. Yes, O Instructor, feed us on Your holy mountain the Church … Such is our Instructor, righteously good. ‘I came not,’ He says, ‘to be served, but to serve’ (Matt. 20:28; Mark 10:45). Therefore He is introduced in the Gospel as ‘wearied’ (John 4:6), because He is toiling for us, and promising ‘to give His life a ransom for many’ (Matt. 20:28). For him alone who does so He owns to be the good shepherd. Generous, therefore, is He who gives for us the greatest of all gifts, His own life; and beneficent exceedingly, and loving to men, in that, when He might have been Lord, He wished to be our brother; and so good was He that He died for us. ”⁷⁵⁶