In an unprecedented gesture last month, Pope Francis kissed the feet of several South Sudanese leaders, who were visiting the Vatican for a retreat, in a plea for peace in the country.

South Sudanese President Salva Kiir told EWTN News that the exchange, which garnered attention around the world, left him “almost trembling.”

“I felt humbled at the humility of the Holy Father, to bend down on the ground and kiss my feet,” Kiir told EWTN News in an interview May 7.

“I was almost trembling because that thing has not happened before, except at the time when Jesus knelt down to wash the feet of his disciples. And it should have been the opposite; his disciples should have been the ones to wash his feet...this is what came into my mind when the Pope knelt down.”