The first Resurrection of the Saints already occurred. Scriptural evidence.

Since scripture clearly states that it is appointed for men to die once, then judgment, What of those who came out of the Graves and made themselves know to the people in Jerusalem, when Jesus was Resurrected?

Hebrews 9
23It was therefore necessary that the patterns of things in the heavens should be purified with these; but the heavenly things themselves with better sacrifices than these. 24For Christ is not entered into the holy places made with hands, which are the figures of the true; but into heaven itself, now to appear in the presence of God for us: 25Nor yet that he should offer himself often, as the high priest entereth into the holy place every year with blood of others; 26For then must he often have suffered since the foundation of the world: but now once in the end of the world hath he appeared to put away sin by the sacrifice of himself. 27And as it is appointed unto men once to die, but after this the judgment: 28So Christ was once offered to bear the sins of many; and unto them that look for him shall he appear the second time without sin unto salvation.

Matthew 27
50Jesus, when he had cried again with a loud voice, yielded up the ghost. 51And, behold, the veil of the temple was rent in twain from the top to the bottom; and the earth did quake, and the rocks rent; 52And the graves were opened; and many bodies of the saints which slept arose, 53And came out of the graves after his resurrection, and went into the holy city, and appeared unto many. 54Now when the centurion, and they that were with him, watching Jesus, saw the earthquake, and those things that were done, they feared greatly, saying, Truly this was the Son of God.

Wave offering
The wave offering or sheaf offering or omer offering was an offering made by the priests to God (Exodus 29:24, 26, 27; Leviticus 7:20-34; 8:27; 9:21; 10:14, 15, etc.). The sheaf or omer or wave-offering then became the property of the priests. [link to en.wikipedia.org (secure)]

They are the wave sheaf offering.

They are with Jesus NOW.

Jesus is High Priest. Revelation 14 tells us what happened to the people who came out of the graves at His Resurrection. NOTE IT USES PAST TENSE VERBIAGE.

Hebrews 6
13For when God made promise to Abraham, because he could swear by no greater, he sware by himself, 14Saying, Surely blessing I will bless thee, and multiplying I will multiply thee. 15And so, after he had patiently endured, he obtained the promise. 16For men verily swear by the greater: and an oath for confirmation is to them an end of all strife. 17Wherein God, willing more abundantly to shew unto the heirs of promise the immutability of his counsel, confirmed it by an oath: 18That by two immutable things, in which it was impossible for God to lie, we might have a strong consolation, who have fled for refuge to lay hold upon the hope set before us: 19Which hope we have as an anchor of the soul, both sure and stedfast, and which entereth into that within the veil; 20Whither the forerunner is for us entered, even Jesus, made an high priest for ever after the order of Melchisedec.

Revelation 14:4
“These are they which were not defiled with women; for they are virgins. These are they which follow the Lamb whithersoever he goeth. These were redeemed from among men, being the firstfruits unto God and to the Lamb.”

The women spoken of in Revelation 14:4 are the apostate churches. It is saying the Saints didn't seek after whores, or if you will, false religion.