Pope Francis just told his brothers in the episcopate that,"Our vocation is to listen to what the Lord is asking us: 'Comfort, comfort my people, says your God” (Isaiah 40:1)'" See here.
What Francis doesn't mention, and this is most significant, is that a Bishop's vocation is primarily one of witnessing to the truth, without which authentic joy is impossible, for joy is a gift of the Holy Spirit (Galatians 5).
Pope John Paul II, in his book entitled "Rise, Let Us Be On Our Way," in a chapter entitled simply "The Shepherd," writes, "Christian tradition has adopted the biblical image of the shepherd in three forms: as the one who carries the lost sheep on his shoulders, as the one who leads his flocks to green pastures, and as the one who gathers his sheep with his staff and protects them from danger.
In all three images there is a recurring theme: The shepherd is for the sheep, not the sheep for the shepherd. He is bound so closely to them, if he is a real shepherd, that he is ready to lay down his life for the sheep (John 10:11). Every year during the twenty-fourth and twenty-fifth week of Ordinary Time, the Liturgy of the Hours presents Saint Augustine's long sermon 'On the Shepherds.' With reference to the Book of the Prophet Ezekiel, the bishop of Hippo strongly rebukes evil shepherds, who are concerned not for the sheep but only for themselves. 'Let us see how the word of God, that flatters no one, addresses the shepherds who are feeding themselves, not the sheep. 'You take the milk, you clothe yourselves with the wool, you slaughter the fatlings; but you do not feed my sheep. The weak you have not strenghtened, the sick you have not healed, the crippled you have not bound up, the strayed you have not brought back, the lost you have not sought; any strong one you have killed; and my sheep are scattered because there is no shepherd.'" (pp. 63-64).
And in the chapter entitled "Courageous in Faith," the Holy Father, citing Stefan Cardinal Wyszynski, writes, "'The bishop has the duty to serve not only through his words and through the liturgy, but also through offering up his sufferings.' Cardinal Wyszynski returned to these thoughts again on another occasion: 'Lack of courage in a bishop is the beginning of disaster. Can he still be an apostle? Witnessing to the Truth is essential for an apostle. And this always demands courage.' These words are also his: 'The greatest weakness in an apostle is fear. What gives rise to fear is lack of confidence in the power of the Lord; this is what oppresses the heart and tightens the throat. The apostle then ceases to offer witness. Does he remain an apostle? The disciples who abandoned the Master increased the courage of the executioners. Silence in the presence of the enemies of a cause encourages them. Fear in an apostle is the principal ally of the enemies of the cause'...Truly, there can be no turning one's back upon the truth, ceasing to proclaim it, hiding it, even if it is a hard truth that can only be revealed at the cost of great suffering. 'You will know the truth, and the truth will set you free' (John 8:32): this is our duty and our source of strength! Here there is no room for compromise nor for an opportunistic recourse to human diplomacy. We have to bear witness to the truth, even at the cost of persecutions, even to the shedding of our blood, like Christ Himself..." (pp. 190-191).
A Bishop has a vocation to discern between good and evil, truth and falsehood, and to judge what is evil and false and to denounce it. The Bishop's vocation is not to sit back out of laziness or fear or both, letting his flock be torn to pieces by rapacious wolves why saying, "Who am I to judge."