'King of Kings' in the Bible

'Artaxerxes, king of kings, to Ezra the priest, a perfect scribe of the law of the God of heaven, and at such a time:

For, thus said the Lord Jehovah: Lo, I am bringing in unto Tyre Nebuchadrezzar king of Babylon, From the north -- a king of kings, With horse, and with chariot, and with horsemen, Even an assembly, and a numerous people.

'Thou, O king, art a king of kings, for the God of the heavens a kingdom, strength, and might, and glory, hath given to thee;

these with the Lamb shall make war, and the Lamb shall overcome them, because Lord of lords he is, and King of kings, and those with him are called, and choice, and stedfast.'

and he hath upon the garment and upon his thigh the name written, 'King of kings, and Lord of lords.'