"You search the Scriptures, for in them you think you have eternal life; and these are they which testify of Me. But you are not willing to come to Me that you may have life” (John 5:39-40 NKJV).
First and foremost of the ways that God speaks are the Scriptures. There should be no controversy among adherents of historic Christianity over this claim, for the Bible is the Word of God. Therefore any discussion concerning the means by which God makes Himself known must begin with the Scripture as a matter of priority, for it alone stands as the final authority on all revelation. Yes, The Bible is our highest court of appeal on all matters of Faith and Doctrine.
There is no oracle, vision, revelation, nor any other thing man claims as being from God that stands above or apart from the Bible, or unanswerable to its sovereign scrutiny. All other means through which God may speak must themselves perfectly align with what the Bible says or we must forthrightly dismiss them as not being from the Lord.
"To the law and to the testimony" Isaiah cried, "if they speak not according to this word there is no light in them!" (Isaiah 8:20).
Clearly the Scripture is vastly superior to all other means of revelation. A dear friend of mine was once approached by a man asking him for a "word from the Lord." My friend thrust his Bible into the man's hand and said, "Here, sir, is a whole Book of words from the Lord! Read it!"
What wonder-working power resides in the Word of God! "Then they cried to the Lord in their trouble, and he saved them from their distress. He sent forth his word and healed them; he rescued them from the grave. Let them give thanks to the Lord for his unfailing love and his wonderful deeds for men" (Psalm 107:19-21)!
Glory to God for the Bible! Would to God that all men everywhere would devote themselves to reading and obeying it, highly esteeming it and humbly advancing its claims.