How do we know that Jesus is the King of Kings?

In Scripture, Jesus is affirmed as the King of Kings, particularly in Psalm 21:5 where it states, 'His glory is great in salvation.' This title is rooted not in human designation but in divine decree. God the Father acknowledges the Son's eternal reign with the declaration, 'Thy throne, O God, is forever and ever.' Furthermore, His sovereignty is continually illustrated throughout the Old Testament and fulfilled in the New Testament as Christ operates as both God and man, leading to the conclusion that He is indeed the sovereign King over all creation and salvation.