Pope Francis on Thursday denounced modern-day Pharisees who are quick to judge other people and despise those who are not like them, saying the path they have chosen is "the root of all wars: all calamities."

Delivering his homily at the daily Mass in the chapel of St. Martha Guesthouse in Vatican City, the pope did not mention by name the specific groups or sectors he was referring to as he spoke in abstract terms about what true Christianity means.

"There are two paths in life: the path of exclusion of persons from our community and the path of inclusion," he said, according to a Catholic News Agency (CNA) article.

The path of exclusion is "the root of all wars: all calamities ... One is excluded from the international community, but also from families, from friends."

On the other hand, the path that brings people closer to Jesus and where true Christianity lies "is contrary to the other: to include," Pope Francis said.

He said to be selective "is not Christian," citing the day's first scripture reading from Romans in which St. Paul chastises those who look down on others.

The Pope castigated those who have the attitude of the Scribes and the Pharisees who regard themselves as perfect in their adherence of the law, while judging others they deem to be sinners.

Pope Francis pointed out that Jesus Christ sacrificed Himself on the cross to save all of mankind, not just a select group of people.

The pope admitted though that having an inclusive attitude is hard to do for some people because "there is that selective attitude" of resistance.

The head of the Roman Catholic Church then cited two parables in the Gospels—the parable of the lost sheep and that of the woman who lost her coin. Both the shepherd and the woman vowed to do anything if only they could regain what they lost. When they eventually found what they were looking for, they were filled with joy. Because they felt joy in their heart, they wanted to express this feeling to other people so they went to their neighbours, their friends to share with them the good news.

The pope described this act as "the 'including' of God."

The opposite of this, he said, is "the exclusion of those who judge, who drive away people."

Pope Francis acknowledged that Christians, including religious leaders, are sometimes guilty of having an exclusion attitude. "We, with our weaknesses, with our sins, with our envy, jealousies, we all have this attitude of excluding which – as I said – can end in wars."

He warned that those who continue to live with a selective and judgmental attitude, which is very much unlike God's attitude of welcome, will one day have to answer for it.

"If I exclude, I will one day stand before the judgment seat of God, I will have to give an account of myself to God," the Pope said.

He urged the faithful to make their best effort not to exclude anyone from their heart, prayer or greeting.

"Never excluding, we have no right!" he said.