Erika Kirk and the message behind the St. Michael's cross she gave to her husband

Soon after she began dating Charlie Kirk, Erika Frantzve -- a devout Catholic -- asked him: "Why don't you wear a cross?"

Kirk's response: "I'm not a jewelry guy." She gave him a St. Michael's Cross, which he started wearing as "he felt the weight of the world on him," Turning Point USA spokesman Andrew Kolvet told Fox News. "He never took it off again, until he was assassinated and the people caring for him ripped it off as they tried to save his life."

The St. Michael's prayer, written in 1898 by Pope Leo XIII, describes fierce warfare between good and evil: "St. Michael the Archangel, defend us in battle. Be our defense against the wickedness and snares of the Devil. … By the power of God, thrust into hell Satan, and all the evil spirits, who prowl about the world seeking the ruin of souls."

Erika Kirk wore that blood-stained pendant during the September 21 memorial service in State Farm Stadium in Glendale, Arizona -- with an estimated 100,000 people inside and thousands gathered nearby. At least 20 million watched on Fox, X and YouTube, with many more using other simulcasts.

In her 30-minute testimony, she said her husband knew his life was in danger, but he stressed the biblical message in a verse from Isaiah: "Here I am, Lord. Send me."

Kirk said she once told him: "Charlie, baby, please talk to me next time before you say that. … When you say, 'Here I am, Lord. Use me,' God will take you up on that.' … God accepted that total surrender from my husband and then called him to His side."

Erika Kirk's address dominated an event that featured President Donald Trump and multiple cabinet members. While praising what Kirk achieved in his 31-year life, several shared how his death has pushed them to ponder their own beliefs.

Farewell to the Prayer to St. Michael the Archangel: Yes, the Latin Mass wars are escalating

Since the late 19th Century, Catholics have recited the Prayer to St. Michael when facing disease, disaster and despair.

It proclaims, in part: "St. Michael the Archangel, defend us in battle. … O Prince of the heavenly hosts, by the power of God, thrust into hell Satan, and all the evil spirits, who prowl about the world seeking the ruin of souls."

Before Vatican II, this prayer was often recited after Mass, although it wasn't in the rubrics. In 1994, St. Pope John Paul II urged Catholics to embrace it -- while preaching on threats to the unborn.

The faithful at St. Joseph's Parish in Libertyville, Ill., stopped reciting the Prayer to St. Michael aloud after Masses this past summer. While debate continues about what the Archdiocese of Chicago instructed, livestreamed remarks by the associate pastor went viral, during a worship wars surge in modern Catholicism.

"What I'm going to say, I'm going to say this with a lot of respect. Following the directive of Cardinal Cupich, we want to remind everyone that the Prayer of St. Michael is not to be said publicly following Mass," said Father Emanuel Torres-Fuentes. "As a priest, I have to obey, and I obey this at peace."

While Cardinal Blase Cupich's actions have made news, this drama opened in July with a Pope Francis apostolic letter entitled "Traditionis Custodes (Guardians of the tradition)." It restricted use of the old Latin Mass, thus undercutting "Summorum Pontificum (Of the Supreme Pontiffs)" by the retired Pope Benedict XVI. That document said the post-Vatican II Novus Ordo was the "ordinary form" for the Mass, but the Tridentine rite was an "extraordinary form" that could be encouraged.

The Pope Francis letter appeared to give local bishops some freedom to control use of the old Latin Mass. Then the Vatican's Congregation for Divine Worship released guidelines on Dec. 18, explaining the pope's edict.

Many bishops, for example, had granted dispensations allowing some diocesan parishes to use the Latin Mass. But Rome's new guidelines said this was not permitted -- only the Vatican could grant exceptions. Also, any parish allowed to celebrate the Tridentine Mass could not list this service in printed or online Mass schedules.