So they disputed. This means that the magicians debated their matter among themselves when they heard this speech, knowing that he could not confront Pharaoh with something like it in all his troops and followers, none of whom would be safe from him except for whom Allah is with. And they kept their conversation secret, meaning their words that they whispered to each other and they were very careful to conceal it, so that Pharaoh and his followers would not become aware of their disagreement, which was necessitated by the wording of the dispute. It is as if it was said: What did they say when their dispute ended?