THE IDENTITY OF THE 144,000
Who are the people in Revelation 7:3? They are called God's servants.
There should be no controversy about the identity of these 144,000 servants of God. Jehovah's Witnesses have tried to falsely claim that 144,000 of their members are to whom this passage is referring. There is simply nothing in the text that would lead to that conclusion. Revelation 7:4-8 could not be clearer that these are 144,000 Israelites divided up 12,000 each from all 12 Jewish tribes.
THE GREAT MULTITUDE
Revelation 7:9-14 describes a great crowd of people of all types from all over the world. They are standing in front of God's throne. That tells you that the scene has shifted from Earth (Revelation 7:1-8) to Heaven. The people in this passage standing before God's throne have white robes, just like the martyrs in Revelation 6 during the fifth seal judgment. Remember when they asked God how long it would be until the Lord avenged their blood? He gave them white robes and told them to wait slightly longer. These people standing before God's throne are the same martyrs. They are standing before God's throne, shouting praises to him with the sound of a collective great roar.
As they continue to praise God, John asks who they are. He finds out that they are martyrs who died in the Great Tribulation. So again, I am not speculating as to who these people are ordering what time these Christians died. Revelation 7:14 makes it abundantly clear.
Their faithfulness to God, even unto death, causes him to bless them with tremendous rewards. Revelation 7:15-17 lists some of those blessings:
The privilege of serving God day and night in his heavenly temple
Shelter
He will satisfy all hunger and thirst. That tells me we will eat and drink in Heaven.
A perfect, comfortable environment
Personal connection with the Shepherd (Jesus Christ)
Springs of life-giving water
He will wipe away their tears
It is not that we will not have any needs or desires in Heaven. The difference is that God will meet all those needs and desires without any burdens we currently experience. As for the tears in Heaven, they remind me of what Jesus said during the Sermon on the Mount. God blesses those who mourn, for he will comfort them (Matthew 5:4).