A missionary is someone who is bound by marriage to the stated mission and purpose of his Lord and Master. He is not to proclaim his own point of view, but is only to proclaim “the Lamb of God.”
But Paul said, “. . . woe is me if I do not preach the gospel!” (1 Corinthians 9:16).
And this is the gospel— “the Lamb of God who takes away the sin of the world!”