They declared to King Nebuchadnezzar, “O king, live forever!
It was strange that Shadrach, Meshach, and Abednego, would be present at this assembly, when, it is likely, they knew for what intent it was called together. Daniel, we may suppose, was absent, either his business calling him away or having leave from the king to withdraw, unless we suppose that he stood so high in the king's favour that none durst complain of him for his noncompliance.
Commenting on Daniel 3:8-18
They spake and said to Nebuchadnezzar,.... Having got access unto him, and within his hearing, they expressed themselves in the following manner: O king, live for ever; this they said to show their fidelity and hearty attachment to him, and their regard to his welfare, and the continuance of his life; and the rather to ingratiate themselves into his affections, and gain audience of him; See Gill on Dan 2:4.
live for ever--A preface of flattery is closely akin to the cruelty that follows. So Act 24:2-3, &c., Tertullus in accusing Paul before Felix.