https://www.btstories.com/conversion-of-saul/

Saul was on a campaign to hunt down and kill those who followed Jesus. He was given authority from the high priest to go to Damascus and bring believers back to Jerusalem.

As he and his men approached Damascus, suddenly a bright light shone around them, and Saul fell to the ground. He heard a voice saying, “Saul! Saul! Why are you fighting against me?”