Revelation 6:9

9 When the Lamb broke open the fifth seal, I saw at the foot of the altar the souls of those whose lives had been sacrificed for [adhering to] the Word of God and for the testimony they had borne.

• Our Father has always allowed us to be killed for His testimony and we will be martyred during the Great Tribulation as well.
• But death for us is a blessing, 1 Corinthians 5:3, 1 Corinthians 15:55, Revelation 14:13.
• We can see that being called to die for Jesus’ sake can be a very great blessing, look at Stephen, Acts 6:15.
• When the fifth seal is broken John sees the souls of everyone who has ever been martyred for Jesus’ sake; John sees their souls, he does not see their bodies. This is important now.
• For this we declare to you by the Lord's [own] word, that we who are alive and remain until the coming of the Lord shall in no way precede [into His presence] or have any advantage at all over those who have previously fallen asleep [in Him in death]. For the Lord Himself will descend from heaven with a loud cry of summons, with the shout of an archangel, and with the blast of the trumpet of God. And those who have departed this life in Christ will rise first. Then we, the living ones who remain [on the earth], shall simultaneously be caught up along with [the resurrected dead] in the clouds to meet the Lord in the air; and so always (through the eternity of the eternities) we shall be with the Lord! 1 Thessalonians 4:15-17 
• How can John only see the souls of the dead here and not their bodies, if there has been a pre-tribulation rapture? If John only saw the souls of the martyred and there had been a rapture, wouldn’t this mean that these people’s bodies and souls would be separate? The Holy Spirit tells us plainly that the dead will be raised first and then those of us who are alive in Christ will be raised. The theory of a pre-tribulation rapture can be debunked with just a couple of scriptures, these in 1 Thessalonians 4, 1 Corinthians 15:52, John 6:39, and Revelation 11:15.
• In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed. 1 Corinthians 15:52
• And this is the will of Him Who sent Me, that I should not lose any of all that He has given Me, but that I should give new life and raise [them all] up at the last day. John 6:39
• The seventh angel then blew [his] trumpet, and there were mighty voices in heaven, shouting, The dominion (kingdom, sovereignty, rule) of the world has now come into the possession and become the kingdom of our Lord and of His Christ (the Messiah), and He shall reign forever and ever (for the eternities of the eternities)! Revelation 11:15
• There is no way that there can be a pre-tribulation rapture and these six verses still be true. The dead in Christ must rise first and the dead in Christ do not rise until the Last Trumpet is blown on the last day. Look at what Jesus Himself spoke in John.
• He who feeds on My flesh and drinks My blood has (possesses now) eternal life, and I will raise him up [from the dead] on the last day. John 6:54
• Jesus said it very clearly, the dead who are in Him, shall not be raised until the last day! The rapture theory says that there are seven years left for this earth to go on as it is after we are gone. The Truth is that we who are alive in Christ cannot be raised before those who have died in Christ. There is no pre-tribulation rapture, and for those who our Father chooses to be here during the Great Tribulation it will be a glorious thing! Because those who are here on the earth in Christ, shall be used in power and demonstration of the Spirit as never before! This is why John only sees the souls of the martyred, because their bodies have not yet been raised up and transformed to be like Jesus.
• But here is another incredibly important Truth, when we are dead we are free from sin, Romans 6:7. Now we may very well be martyred for Christ’s sake. But the glorious Truth is that each and every one of us who has been called and chosen is dead right now, Galatians 2:20, Colossians 3:3. So right now, this very moment our lives have been sacrificed so that we are able to serve without the hinderance of sin. We are dead to sin, just as Jesus is dead to sin, Romans 6:11. 
• There are going to be untold millions of people who are saved during the Great Tribulation. So the Truth is that there is going to be an uncountable number of people who are sacrificed from the cares of this world to serve as we never have been used to serve before.