Revelation 4:1

After these things I saw, and behold, a door opened in heaven; and the first voice which I heard was as of a trumpet speaking to me; and it said, Come up hither, and I will shew thee things which must come to pass hereafter.

Revelation 1:10

Here I was in the Spirit on the Lord's-day: and heard behind me a loud voice, as of a trumpet,

Revelation 1:19

Write what thou hast seen, the things which are, and which are to be hereafter."

Revelation 11:12

And they heard a great voice from heaven, saying to them, Come up hither; and they ascended up to heaven in a cloud, and their enemies beheld them.

Revelation 22:6

And he said unto me, These words are faithful and true: and the Lord God of the holy prophets hath sent his angel to shew unto his servants what must soon be.

Matthew 3:16

Then he permitted Him. And Jesus as soon as He was baptized came up from the water; and behold, the heavens were opened unto Him, and he saw the Spirit of God descending like a dove, and coming upon Him:

Mark 1:10

and as soon as He came up from the water, he saw the heavens opened, and the Spirit like a dove descending upon Him.

Luke 3:21

Now, when all the people were baptized, and Jesus was baptized and praying,

Acts 7:56

and he said, Behold, I see the heavens opened, and the Son of man standing at the right hand of God.

Acts 10:11

and some thing descending to him, like a great sheet tied at the four corners, and let down to the earth:

Revelation 16:17

And the seventh angel poured out his vial into the air; and there came forth a great voice out of the temple of heaven, from the throne, saying, It is done.

John 16:13

But when the Spirit of truth is come, He will guide you into all truth: for He will not speak of Himself; but whatsoever He shall hear, that will He speak, and will shew you things to come.

Revelation 1:1-3

The Revelation of Jesus Christ, which God gave unto Him, to shew to his servants things which must shortly come to pass; and He sent and signified it by his angel to his servant John,

Treasury of Scripture Knowledge

Summary

After this I looked, and, behold, a door was opened in heaven: and the first voice which I heard was as it were of a trumpet talking with me; which said, Come up hither, and I will shew thee things which must be hereafter.

Bible References

A door

Matthew 3:16
Then he permitted Him. And Jesus as soon as He was baptized came up from the water; and behold, the heavens were opened unto Him, and he saw the Spirit of God descending like a dove, and coming upon Him:
Mark 1:10
and as soon as He came up from the water, he saw the heavens opened, and the Spirit like a dove descending upon Him.
Luke 3:21
Now, when all the people were baptized, and Jesus was baptized and praying,
Acts 7:56
and he said, Behold, I see the heavens opened, and the Son of man standing at the right hand of God.
Acts 10:11
and some thing descending to him, like a great sheet tied at the four corners, and let down to the earth:

The first

Revelation 1:10
Here I was in the Spirit on the Lord's-day: and heard behind me a loud voice, as of a trumpet,
Revelation 16:17
And the seventh angel poured out his vial into the air; and there came forth a great voice out of the temple of heaven, from the throne, saying, It is done.

And i

Revelation 1:19
Write what thou hast seen, the things which are, and which are to be hereafter."
Revelation 22:6
And he said unto me, These words are faithful and true: and the Lord God of the holy prophets hath sent his angel to shew unto his servants what must soon be.
John 16:13
But when the Spirit of truth is come, He will guide you into all truth: for He will not speak of Himself; but whatsoever He shall hear, that will He speak, and will shew you things to come.