Francis had invited homeless and impoverished people to one of his last Masses during the Holy Year of Mercy he established to stress that virtue.
The Holy Year ends on November 20.
Along with cardinals and other prelates, homeless people sat near the ornate central altar.
In his homily, Francis said God and our neighbour are the most valuable riches in life.
The Pontiff elaborated on his recent comments encouraging social policies of inclusion, amid a backdrop of the rising popularity of politicians advocating exclusionary policies toward migrants of different religions, races or ethnicities in several developed countries.
“It is ominous that we are growing used to this rejection,” the Pope said. “We should be worried when our consciences are anaesthetised and we no longer see the brother or sister suffering at our side, or notice the grave problems in the world, which become a mere refrain familiar from the headlines on the evening news.”
He called it a “symptom of spiritual sclerosis” when people focus on producing goods instead of loving others.
“This is the origin of the tragic contradiction of our age: as progress and new possibilities increase, which is a good thing, fewer and fewer people are able to benefit from them,” the Pope said. He called that contradiction a “great injustice.”
“There is no peace in the homes of the prosperous as long as justice is lacking in the home of everyone,” he added.