Sparks of persecution cause the Gospel fire to spread
Acts 8:1–4 (ASV 1901)
And Saul was consenting unto his death. And there arose on that day a great persecution against the church which was in Jerusalem; and they were all scattered abroad throughout the regions of Judaea and Samaria, except the apostles. 2And devout men buried Stephen, and made great lamentation over him. 3But Saul laid waste the church, entering into every house, and dragging men and women committed them to prison.
4They therefore that were scattered abroad, went about preaching the word.
Acts 11:19 (ASV 1901)
19They therefore that were scattered abroad upon the tribulation that arose about Stephen travelled as far as Phoenicia, and Cyprus, and Antioch, speaking the word to none save only to Jews.
Philippians 1:14 (ASV 1901)
14and that most of the brethren in the Lord, being confident through my bonds, are more abundantly bold to speak the word of God without fear.