VATICAN CITY (CNS) — When boasting of having Jesus Christ as one’s savior, people shouldn’t pretend they aren’t guilty of sin, Pope Francis said in a morning homily.

The sincere and humble admission of one’s weaknesses, of having “a sliver of Satan in my flesh,” shows that the power of salvation comes from God, not oneself, the pope said at Mass June 14 in the chapel of the Domus Sanctae Marthae.

The pope concelebrated Mass with Cardinal Mauro Piacenza, prefect of the Congregation for Clergy; those in attendance at the Mass included members of the clergy office.

The pope highlighted the day’s reading from St. Paul’s Second Letter to the Corinthians in which the apostle said, “We hold this treasure in earthen vessels that the surpassing power may be of God and not from us.”

In fact, the only way to truly receive the gift of salvation is in “an earthen vessel,” that is, in recognizing one’s own sinful nature with real humility, the pope said.

“The dialogue of salvation” happens between Christ and people exactly “as we are,” he said.

He said when St. Paul spoke to the people, he always referred to his past mistakes and sinful nature, and never insinuated that “‘Now I am a saint.’ No. Even now a sliver of Satan in my flesh” remains.

St. Paul “is a sinner who welcomes Jesus Christ, speaks with Jesus Christ.”

The key to sharing Christ with others is humility, which all priests should reflect, Pope Francis said.

“If we only boast about our resume and accomplishments and nothing else, we will end up being mistaken. We cannot proclaim Jesus Christ the Savior because in the end we don’t feel it” if people don’t really experience salvation, he said.

People have to demonstrate “real humility” and repentance for specific, concrete sins, and not be “sinners with that humility that looks more like a little angel face. No, intense humility,” he said.

If Christians and priests cannot achieve this humility and make “this confession to themselves and the church, then something is wrong;” and the first thing that will fail is “understanding the beauty of the salvation Jesus brings us.”

“We have a treasure — Jesus Christ the Savior, the cross of Jesus Christ, that we are proud of,” he said. “But we hold it in an earthen vessel.

“Jesus Christ didn’t save us with an idea, with an intellectual program, no. He saved us with his flesh, with the concreteness of the flesh.”

And it is only in the flesh, “in earthen vessels that one can understand, one can receive” Christ’s gift of salvation, he said.