The first use of the Greek term "tribulation" is seen when Jesus teaches the Parable of the Sower.
The one on whom seed was sown on the rocky places, this is the man who hears the
word and immediately receives it with joy; yet he has no firm root in himself, but is only temporary, and when
affliction or persecution arises because of the word, immediately he falls away. (Matt 13:20-21;
Mark 4:16-17)
Here Jesus indicates that "affliction" or "tribulation" describes the persecution of one's
faith in God, and He exclusively applies the term to Believers; thus, limiting its use to the persecution of
one's faith. This makes a distinction from other causes of persecution (i.e. racism, socio-economic class, etc.).
When studying Revelation, there are 3 instances when human beings are mentioned in the Temple of God. In each
instance, these human beings appear to be those who were martyred before and during the Great Tribulation, which
were either Believers who died for their faith or the 144,000 bond servants (Rev 6:9-11;
Rev 7:13-15; 14:1-3).
It is significant to note that those Believers who were martyred for their faith before Jesus Christ returns
reside underneath the altar in the Temple of God and emerge later, when Jesus breaks the seals, to receive their
white robe and serve God Himself.
When the Lamb broke the fifth seal, I saw underneath the altar the souls of those
who had been slain because of the word of God, and because of the testimony which they had maintained; and
they cried out with a loud voice, saying, "How long, O Lord, holy and true, will You refrain from judging and
avenging our blood on those who dwell on the earth?" And there was given to each of them a white robe; and they
were told that they should rest for a little while longer, until the number of their fellow servants and their
brethren who were to be killed even as they had been, would be completed also. (Rev 6:9-11)
Then one of the elders answered, saying to me, "These who are clothed in the white
robes, who are they, and where have they come from?" I said to him, "My lord, you know." And he said to me,
"These are the ones who come out of the great tribulation, and they have washed their robes and made them
white in the blood of the Lamb. For this reason, they are before the throne of God; and they serve Him day and
night in His temple; and He who sits on the throne will spread His tabernacle over them.
(Rev 7:13-15)
Then I looked, and behold, the Lamb was standing on Mount Zion, and with Him one
hundred and forty-four thousand, having His name and the name of His Father written on their foreheads. And
I heard a voice from heaven, like the sound of many waters and like the sound of loud thunder, and the voice
which I heard was like the sound of harpists playing on their harps. And they sang a new song before the throne
and before the four living creatures and the elders; and no one could learn the song except the one hundred and
forty-four thousand who had been purchased from the earth. (Rev 14:1-3)