How then will they call on Him in whom they have not believed? How will they believe in Him whom they have not heard? And how will they hear without a preacher? How will they preach unless they are sent? Just as it is written, “HOW BEAUTIFUL ARE THE FEET OF THOSE WHO BRING GOOD NEWS OF GOOD THINGS!”Romans 10:14-15

The sine-qua-non for faith is hearing which boils down to a preacher who is sent.

 Pray that those the Lord has sent will be obedient to the heavenly vision.
 Pray that many who hear them will believe their message.
 Pray that no confusion of any kind will attend their ministry.