Desperation versus sincere faith

وَقَالُوا۟ يَـٰٓأَيُّهَ ٱلسَّاحِرُ ٱدْعُ لَنَا رَبَّكَ بِمَا عَهِدَ عِندَكَ إِنَّنَا لَمُهْتَدُونَ

And they said [to Moses], "O magician, invoke for us your Lord by what He has promised you. Indeed, we will be guided."