Marraige is not by religion.

BIBLE MEANS WORLD HINDUISM.
QURAN MEANS WORLD HINDUISM.
GITA MEANS WORLD HINDUISM.
GURU GRANTH SAHIB MEANS WORLD HINDUISM.
BUDDHA'S 8 FOLD PATH MEANS WORLD HINDUISM.
JAINISM'S "ALL CASTES ARE EQUAL" MEANS WORLD HINDUISM.

SO MARRAIGE CERTIFICATE IS NOT AS PER RELIGION.