Catholics in Los Angeles celebrated all that St. Peter Claver achieved on his feast day recently.

“St. Peter Claver baptized and taught the faith to over 300,000 slaves over a period of 40 years,” the Archdiocese of Los Angeles tweeted Friday.

In 1581, St. Peter Claver was born in Verdú, Spain. He became a Jesuit priest in 1616 and was sent to Cartagena, Colombia, to serve as a missionary. There, Peter had first-hand experience dealing with the horrors of the slave trade. Seeing those things, he dedicated himself to helping those who were enslaved, Britannica explains.

He spread the Catholic faith while taking care of the sick in his interactions with the slaves in Colombia. It is said that he converted and baptized about 300,000 slaves in his years there. He died in 1654 in Cartagena.

Pope Leo XIII canonized St. Peter Claver in 1896 and declared him “patron of all Roman Catholic missions to African peoples” Britannica adds.

Jesuits.org discusses St. Peter Claver and the role he played as a missionary to slaves during a time when European colonists went along with the slave trade in opposition to Pope Paul III’s condemnation of it. The Jesuits (Society of Jesus) admit that their order enslaved many during that time. Today, they refer to the period as a “deeply regretful chapter” in the group’s history.

St. Peter’s approach to the enslaved was simple. “We must speak to them with our hands before we try to speak to them with our lips.” He baptized many children on the slave ships that he lived on.

St. Peter is reported to have had healing powers, a gift accredited to his humility and dedication to the less fortunate, Jesuits.org says. He healed the sick much like Christ did, it says.

John Grondelski, writing for the National Catholic Register (NCR), asserts that St. Peter Claver’s life is an example of perseverance while the Church and the state battled over the issues of slavery.

“It would still take three centuries for much of the world to recognize the incongruity between human dignity and slavery, something Claver already knew,” Grondelski writes in the article. “And slavery continues, in various forms under different names, today. Our own society, too, can be blind to its moral failings: I am certain there will be a day when people look back on the 20th and 21st century to ask, ‘How could they believe killing their unborn babies was a ‘human right?’ Perhaps we still have something to learn from Peter Claver: about persistence in our time and patience in God’s.”