Words of fire
Jeremiah 1:9 (Berean Study Bible)
Behold, I have put my words in your mouth.
As witnesses unto the Lord Jesus Christ we have no business speaking our words but His. A child of God who has been baptized in the Holy Spirit and fire is given the "words of fire" from heaven. The word of God is the power of God to recreate this fallen universe and comes with His omnipotence. When the Holy Spirit descended on the day of Pentecost, lay fishermen became powerful orators for Christ. An old man like Moses who had slurred speech shook the foundations of Egypt with his powerful proclamations. A saint speaks God's words in the Holy Spirit and they are not philosophical musings but have the omnipotence of the Creator in them.