After getting through many angels and the powerful angel Seraph in many battles in Purgatorium you finally came to a room to finally stop the gods law path until you finally hear a voice… a Chaste voice was heard a distant away…

…I suspected that we would meet. My former brother, blinded and consumed by pride, and the pitiful son of man who sold his soul to the demons.

He finally shows himself

I am the Lord's chariot...the seraph Merkabah. Foolish ones who churlishly refuse the hand of salvation that the lord has extended to you...I shall reduce you to ash for the sake of a new millennium of order.

It seems Jonathan sacrificed himself to Uriel, Raphael, Gabriel and Michael, summoning Merkabah.

Fall into the abyss!