Miraculous and Strange Encounters

These five families along with their adult friends seem unique in their love for God and for their Bible study teacher, Mrs. Ruth, but all of them, including the teacher, are introduced to someone who calls himself Obadiah and seems very strange indeed! However, in the course of time, everyone seems to fall in love with this man so deeply they're saddened and devastated when he suddenly, one evening, leaves them in quite an unusual and most unsuspected way.

Who was this man, where did he come from, and why did he come to them?