A prophet must always be person who not only "is able to cry for his people, but also capable of taking risks to speak the truth," the Pope said in his homily April 17 at morning Mass in the Domus Sanctae Marthae.

The church "needs us to be prophets. Not critics, that's another thing. "One thing is to be the critical judge who likes nothing, who doesn't like anything," he said. "That is not a prophet."

In his homily, the Pope reflected on the day's first reading from the Acts of the Apostle, which recounted St. Stephen's martyrdom.

The first martyr of the church was stoned to death after denouncing the elders and scribes as "stiff-necked people" who "always oppose the Holy Spirit."

Truth, Pope Francis said, is always "uncomfortable" and when a prophet speaks the truth, hearts can either open or "become more like a rock, unleashing anger, persecution."

The Pope noted that while Jesus also reprimanded people at times with harsh words, even calling them a "perverse and adulterous generation," he also cries for them, as he did when he wept for Jerusalem.

"This is the test," the Pope said. "A true prophet is one who is able to cry for his people and speak strongly when he must speak (the truth). He is not lukewarm, he is always like that -- direct."

However, like St. Stephen and many others who were martyred, a "true prophet, if he does his job well, risks his own skin" so that others may find hope, Pope Francis said.

"May this service of prophecy never lack in the church so that we may always go forward," the Pope said.