24 Heb “What is this deed you have done?” The demonstrative pronoun (“this”) adds emphasis to the question. A literal translation seems to contradict the following statement, in which Joseph affirms that he is able to divine such matters. Thus here the emotive force of the question has been reflected in the translation, “What did you think you were doing?”
25 Heb “[is] fully able to divine,” meaning that he can find things out by divination. The infinitive absolute appears before the finite verb for emphasis, stressing his ability to do this.

In other versions

Joseph said to them, “What deed is this that you have done? Do you not know that a man like me can indeed practice divination?”

Joseph said to them, “What is this you have done? Don’t you know that a man like me can find things out by divination?”

“What have you done?” Joseph said to them. “Didn’t you know that a man like me could uncover the truth by divination?”

“What have you done?” Joseph demanded. “Don’t you know that a man like me can predict the future?”

Then Joseph said to them, “What is this deed that you have done? Did you not know that a man who is like me surely practices divination?”

And Joseph said unto them, What deed is this that ye have done? wot ye not that such a man as I can certainly divine?

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