The last time a pope and a politician got into such a battle may have been when Henry VIII kicked the Catholic Church out of England. Donald Trump called Pope Francis too political for visiting the U.S.-Mexico border and now the pope is suggesting the Trump "is not Christian" if he wants to build a wall to keep immigrants out.

Trump's immediate response to Pope Francis suggesting he's "not a Christian" if he wants to build a wall on the U.S. border with Mexico is that the pontiff apparently only knows half the story of the problems with illegal immigration. Trump called it "disgraceful" in a Facebook post and suggested Francis should be praying for a Trump presidency to protect the Vatican from an ISIS attack.

Pope Francis made his comments on his flight from Mexico, hours after he presided over Mass in the Mexican border city of Ciudad Juárez. He placed flowers at a memorial on the Rio Grande commemorating those who have died trying to cross into the United States.

"A person who thinks only about building walls, wherever they may be, and not building bridges, is not Christian," Francis told reporters. "This is not in the Gospel."

While he said he had not heard specifically about Trump's wall proposal, he offered to "give him the benefit of the doubt." But then he added "I'd just say that this man is not Christian if he said it this way."

A Trump advisor soon tweeted foul, noting that Vatican City is surrounded by a wall intended to keep people out.

Amazing comments from the Pope- considering Vatican City is 100% surrounded by massive walls. pic.twitter.com/g3iVLDVGe5

-- Dan Scavino (@DanScavino) February 18, 2016

Ironically, written on the Vatican wall is the biblical verse Matthew 7:3:
"And why beholds thou the mote that is in my brother's eye, but considers not the beam that is in thine own eye?"

Read also: Is Donald Trump Right? Is Pope Francis Too Political?

"A man who lives in a city-state completely surrounded, literally, by giant walls-Vatican City is literal fortress." https://t.co/rCmpP2FaKP

-- Dan Scavino (@DanScavino) February 18, 2016