Daniel 2:30 (ESV)

30 But as for me, this mystery has been revealed to me, not because of any wisdom that I have more than all the living, but in order that the interpretation may be made known to the king, and that you may know the thoughts of your mind.

The only true God puts the words into Daniel’s mouth. This God will make known what dwells in Nebuchadnezzar’s heart and what his answer is to him. The king has been worrying as he ponders the future of his kingdom and his power, especially when in his sleep he saw that grand image.