Thus saith the Lord… – various scriptures

It is in the Word that we must find wisdom and power, “because the foolishness of God is wiser than men; and the weakness of God is stronger than men.” The faintest whisper of Jehovah’s voice should fill us with a solemn awe and command the deepest obedience of our souls. Brethren, how careful should we be that we do not set up in God’s temple anything in opposition to His Word, that we do not permit the teachings of a creature to usurp the honor due to the Lord alone! “Thus saith antiquity,” “thus saith authority,” “thus saith learning,” “thus saith experience,”-these be but idol-gods, which defile the temple of God; be it yours and mine, as bold iconoclasts, to dash them in pieces without mercy, seeing that they usurp the place of the Word of God. “Thus saith the Lord “-this is the motto of our standard, the war-cry of our spiritual conflict,-the sword with which we hope yet to smite through the loins of the mighty who rise up against God’s truth. Nothing shall stand before this weapon in the day when God cometh out of His hiding-place; for even at this hour, when “Thus saith the Lord” sounds from the trumpet of the Lord’s ministers, the hosts of Midian begin to tremble; for well they know the might of that terrible watchword in days of yore.

Let me say to you, my hearers, have any of you a hope of heaven which will not stand the test of “Thus saith the Lord?” What are you resting upon? Are you building upon your own works? Are you depending upon your own feelings? Do you rely upon sacraments? Are you placing your trust upon the word of man? If so, remember that when God shakes all things, He will shake these false foundations; but oh! build upon the Word of my Lord and Master; trust your soul with Jesus. ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/0591.cfm