St. Ciaran of Clonmacnoise was St. Kevin's soul-friend, and they were very close. When Ciaran approached death, he said: "Let me be carried to a small height." Then angels went to meet his soul, filling as they did all the space between heaven and earth. He was carried back into the little church, and raising his hands, he blessed his people. Then he told the brethren to shut him up in the church until Kevin should come from Glendalough.
Kevin arrived three days after Ciaran's death, having left his monastery as soon as he heard that his closest friend was dying, but he had been very delayed. At once Ciaran's spirit returned from heaven and reentered his body so that he could commune with Kevin and welcome him. The two friends stayed together for a long time, engaged in mutual conversation, and strengthening their friendship.
Excerpted from: https://orthodoxwiki.org/Kevin_of_Glendalough
