“And to the angel of the church in Pergamos write; These things saith he which hath the sharp sword with two edges;” (Revelation 2:12)
As already stated in the post regarding Revelation 1:16, the sharp two-edged sword represents the Word of God that proceeds from Jesus’ mouth:
“For the word of God is quick, and powerful, and sharper than any two-edged sword, piercing even to the dividing asunder of soul and spirit, and of the joints and marrow, and is a discerner of the thoughts and intents of the heart.” (Heb 4:12)
This time Jesus is emphasizing to the messenger/angel of the church the authority of his Word, because there are now amongst them at Pergamos men who thought they could get away with modifying and changing the Word of God for their own benefit. He emphasis to them Jesus is “he which hath the sharp sword with two edges.” No one has authority or the privilege to modify his word. It belongs to him, and anyone modifying it will suffer the severe consequences. The “seat” for all authority (including the Word of God) rests only with Jesus Christ “the author and finisher of our faith” (Hebrews 12:2).