God, who at various times and in various ways spoke in time past to the fathers by the prophets, has in these last days spoken to us by His Son, whom He has appointed heir of all things, through whom also He made the worlds… Hebrews 1:1-2
God’s revelation of Himself is absolutely essential. Had God not been pleased to reveal Himself to those who bear His image (human beings), we would know no more about God than so many amoebas. His revelation of Himself has been progressive, revealing more and more of Himself throughout the ages, all pointing to the most perfect revelation of Himself in the Person of Jesus Christ.
Before the revelation on Himself in Christ, God spoke in times past in various ways, but that revelation concluded with Christ and with the subsequent record of Christ in the Bible.
There is no further revelation of God beyond Christ and the scriptures. Yes, when Christ comes again and we see Him, our reception and understanding of Him will be enhanced as never before; but even then, it will not be a revelation of more of Christ as much as us simply having greater understanding of what has already been revealed in Christ.
Has revelation ceased? God’s last word was God’s last word. Jesus is God’s last word and the NT is the record of Christ. There is therefore now no new revelation until the Lord returns. All messages that claim to be from God must be checked by and agree with Scripture. Therefore, as John Owen pointed out, if a supposedly new revelation disagrees with Scripture, it is false; and if it agrees, it is not new and is unnecessary.
Let us endeavor to grow in the grace and knowledge of our Lord and Savior Jesus Christ. To Him be the glory both now and forever. Amen. 2 Peter 3:18