Oh, that's a fine example of The Two Swords Theory.

The sword he grips in his left hand represents the  so called temporal authority and the object in his right hand symbolises ecclesiastical authority. This understanding originates from the letter written by Pope Gelasius I in 494 to the byzantine emperor Anastasius Dicorus. In this letter he stated that the world consists of two powers: spiritual and secular authority. Christians owed obedience to all authority but their duty to God trumped that to secular power. F.e they couldn't decide wether they should suffer tyranny as a test of faith or should oppose tyrants as ungodly rulers.

It was put into this metaphor: Church received the sword of spiritual authority symbolizing responsibilty for guiding humanity to salvation. The state was given the sword of power to maintain order in the realm and to help the church perform its role.

This division of responsibilities and power was often depicted in art, although this image differs a little bit from the regular examples. Basically you would see Christ/Saint atop handing the swords (could be something else: pallium, flags etc.) to the kneeling Pope and the Emperor, accordingly to the two swords theory.

Here however we see both symbols of powers given to the emperor so that's ruining the whole theory and implementing disorder. We see the overpowered king who is in charge of both spiritual and secular power. The clergymen (maybe pope and anti pope) are only helping him wield these power. This basically states pope has no power. He is subordinated to emperor and his role is to merely help the secular king.

There's a high probability Henry wanted to be depicted that way, this sends a strong message he's wielding the whole power.