Revelation mentions patient endurance seven times. At the book's beginning, John sets the tone by introducing himself as "I, John, your brother and companion (sharer and participator) with you in the tribulation and kingdom and patient endurance [which are] in Jesus Christ" (Revelation 1:9, Amplified Bible). The construction here is peculiar, but John uses three words to describe one thing—namely, the tribulation that is connected with the Kingdom and which requires patient endurance (see Acts 14:22; II Timothy 2:11-12).
In the letters to the seven churches, several recurring phrases or themes appear. They all contain "I know your works" and "He who has an ear, let him hear what the Spirit says to the churches." Five letters contain the command to repent, and "patience" appears four times in three of them, a good indicator of the importance of patience to God's church, especially at the end time.
In addition to the mention in Revelation 3:10, Christ commends the church at Ephesus for its patience:
I know your works, your labor, your patience, and that you cannot bear those who are evil. And you have tested those who say they are apostles and are not, and have found them liars; and you have persevered and have patience, and have labored for My name's sake and have not become weary. (Revelation 2:2-3)
As the prophecies of the end time unfold, the patience of the saints is highlighted twice more. The first is in Revelation 13:9-10: "If anyone has an ear, let him hear. He who leads into captivity shall go into captivity; he who kills with the sword must be killed with the sword. Here is the patience and the faith of the saints."
In the preceding verses, John describes the Beast, his power, and his blasphemy. God allows him to make war with the saints and overcome them. This is part of what the saints will have to endure. Some translations, like The Amplified Bible and the English Standard Version (ESV), end verse 10 with "Here is a call for the endurance and faith of the saints," which fits exactly with Christ's "command to persevere" (NKJV) or "[keeping] the word of [His] patience."
The first part of verse 10 can be confusing because, even though the book was written in Greek, John is actually using a Hebrew idiom that signifies the certainty of approaching judgment. This can be seen in Jeremiah 43:11; 15:2.
This Hebraism means that it is so certain that the Beast will carry out these things that none will escape being involved in some way. Thus, God calls for endurance and faith.
Revelation 14:12 contains another reference to the perseverance of the saints: "Here is the patience of the saints; here are those who keep the commandments of God and the faith of Jesus."
The saints are defined as those who keep God's law and maintain and give attention to the faith of Jesus. Again, the context is the time when the world will worship the Beast and receive his mark. As in Revelation 13:10, translations such as the ESV render the first part as "Here is a call for the endurance of the saints," meaning that, when the saints see this occurring, their endurance and perseverance will be in greatest need.