(Swaad) 38 : 20
وَشَدَدْنَا مُلْكَهُ وَآتَيْنَاهُ الْحِكْمَةَ وَفَصْلَ الْخِطَابِ
And We empowered his kingship to him, and We gave Him the Wisdom, and eloquence in speech.
See explanation 2: 251 and 21: 78-80.