Christendom

noun3

1. •
   The Christian world; Christ's Church on Earth.

   • The Arian doctrine which then divided Christendom. — 1670
2. •
   (no longer used) The state of being a (devout) Christian; Christian belief or faith.

   • By my Christendome, So I were out of prison, and kept Sheepe, I should be as merry as the day is long. — 1596
3. •
   (no longer used) The name received at baptism; any name or appellation.

   • His faith, his sweet disaster: with a world Of pretty fond adoptious christendomes That blinking Cupid gossips. — 1604