Overall meaning :
Allah, Exalted be He, points out that the magicians who had been summoned from the cities, came to Pharaoh and said to him, 'Will you give us a reward if we defeat Moses?’ 'Yes,’ he answered. 'and you will certainly be among those closest to me.’
Addressing Moses, they said, 'Either you cast down your staff first, or we will cast down ours first.’ Moses told them to throw their rods first. And when they did, they bewitched people’s eyes and terrified them by a display of mighty magic.