What is "The Hour of Temptation"? – by Dr. Renald Showers – www.ankerberg.org/Articles/biblical-prophecy/BP1104W1.htm
What does Jesus mean by the phrase "the hour of temptation"?
Revelation 3:10: Jesus is making a promise to Christians and He says, in verse 10, "Because you have kept the word of my patience, I also will keep you from the hour of temptation." Literally, the hour of testing "which shall come upon all the world to try them that dwell upon the earth." Literally, "to try the earthdwellers." Notice, He’s saying here that He will keep His saints, His true believers, out of the hour of testing.
Now, many scholars agree that the testing here is referring to a future period of wrath upon the face of the earth. It’s obviously referring to a time period because He talks about the "hour" of testing. So many agree that He’s promising here to believers to keep them out of that hour of testing.
But some say, "Well, it’s just the testing that He’s preserving them from. They’ll be here during the time of the testing, but God somehow will shelter them or protect them from the testing."
But notice John doesn’t say here, quoting the Lord’s promise, that He will deliver them or keep them out of the testing, He says He will keep them out of "the hour of testing." In other words, He will keep them out of the very time period when the testing is taking place.
And then He says here the purpose of that time period of testing, the purpose is not to do something with regard to Church saints, but the purpose of that hour of testing is to test or to try the earthdwellers. When you go through the book of Revelation, the earthdwellers consistently is referring to rebellious unsaved people who refuse to repent and who are so hardened against God that they will never repent. They will never get saved.