When the first seal was opened, what did the rider of the white horse hold?

Answer: A bow

The white horse's rider held a bow and was given a crown. The red horse's rider got a sword; the black horse's rider held scales.

“Then I watched as the Lamb opened one of the seven seals, and I heard one of the four living creatures say in a voice like thunder, “Come!” So I looked and saw a white horse, and its rider held a bow. And he was given a crown, and he rode out to overcome and conquer.”— Revelation 6:1-2 (BSB)