What is the explanation of revelation 3 8?

Answer 1

Revelation 3 as far as I know is the third chapter of the Book of Revelation also called the Book of Revelation of John the Divine. If you mean some other book by that name I am not aware of one. Chapter 3 has 3 letters of 7 letters John was instructed to write to 7 different Churches in the early Church. Chapter 3 contains the letter to the church in Sardis, the letter to the Church in Philadelphia, and the one to the church in Laodicea. Writing to the "angel" in each case was writing to the messenger, the main speaker, or head, of each church. I am not sure what it is you want illuminated. The groups in Sardis thought they were doing what God wanted of them, and weren't "yet you have a few there" who wear white clothes. That means they live by trusting God instead of trying to please what ever humans wanted of them, first of all. And Jesus promises not to remove those peoples names from the record of them named already for eternal life. The letter to the assemby in Philadelphia is the only letter out of the whole 7 that contains no critique. It is full of exhorting to hold on, keep the faith, keep on keeping on though they have little power, and promises of help and salvation, even honor in heaven. The letter to the Laodicean's is the most scary one. Those people are like the frog in the pan on a stove being heated up slowly and not noticing what terrible trouble they are in. It is a hard thing to be abused for holding fast to faith in the One true God, and/or His Son. But doing so comes with great blessings. It is a whole different matter to end up having God Almighty against you. That is why God is saying for them to pick/chose. Those who go on fire for the Lord will, at least, not end up with it being God working against them. Few get grace to endure it there.

Answer 2

"Write this letter to the angel of the church in Philadelphia. This is the message from the One who is Holy and True. He is the One who has the key of David. He opens doors, and no one can shut them; He shuts doors, and no one can open them. 'I know all the things you do, and I have opened a door for you that no one can shut. You have little strength, yet you obeyed My Word and did not deny Me." (Rev.3:7-8 NLT New Living Translation)

"...The same Lord Jesus has the key of government and authority in and over the church. He opens a door of opportunity to his churches; he opens a door of utterance to his ministers; he opens a door of entrance, opens the heart. He shuts the door of heaven against the foolish, who sleep away their day of grace; and against the workers of iniquity, how vain and confident soever they may be. The church in Philadelphia is commended; yet with a gentle reproof. Although Christ accepts a little strength, yet believers must not rest satisfied in a little, but strive to grow in grace, to be strong in faith, giving glory to God..." (Matthew Henry's Concise Commentary: Revelation 3; Epistles to the church/ at Philadelphia; vv. 7--).