Was There Ever a Living Saint?

No, the process of canonization is lengthily and a review of the circumstances surrounding a person's death would be extensive. Mother Teresa was considered a "living saint" within her lifetime, but that was an editorial description, not a legitimate title by the Catholic Church.

Is there a saint alive?

The altar in an Orthodox church usually contains relics of saints, often of martyrs. ... Because the Church shows no true distinction between the living and the dead (the saints are considered to be alive in Heaven), saints are referred to as if they were still alive. Saints are venerated but not worshipped.

What is a living saint called?

image source, AP. Hundreds of miracles have been attributed to the late Mother Teresa. When she was alive, Mother Teresa was called "a living saint".