pan-Christian
/ˌpanˈkrɪstʃ(ə)n/noun
Originally: (probably) a Christian pantheist. Now: a supporter of Christian ecumenism. rare.
adjective
Of, relating to, or involving all of the different Christian denominations; ecumenical, interdenominational.
Origin
Mid 19th century; earliest use found in The Edinburgh Review. From pan- + Christian.