Revelation 14:13 And I heard a voice from heaven saying unto me, Write, Blessed are the dead which die in the Lord from henceforth: Yea, saith the Spirit, that they may rest from their labours; and their works do follow them.
This verse refers specially to those believers who are killed by the anti-Christ government during the Tribulation period, but before the Seven Bowls of Wrath. The totality of Tribulation Period saints are in, and martyred. During the Seven Bowls of Wrath there will no one be saved, for all are destined for and are experiencing the wrath of God.
So Revelation 14:13 is speaking in reference to the Tribulation martyrs. Their number is not yet complete. Hence, "Blessed are the dead which die in the Lord from henceforth." As with all who die in the Lord, they rest from their labours, and "their works do follow them."
How do the works follow them? The knowledge of their works, known to God, persist into Heaven. Their sins have already been washed away in the Blood of Jesus, shed at Calvary. So their sins do not follow them. Hence the works in question are good works, rewardable works, gold, silver and precious stones.
Obviously, they will receive their rich reward, and the reward and the sight of the Lord Jesus, and the opportunity to serve Him for the rest of Eternity, will make all their sufferings seem more than worthwhile..