Ezekiel 44:15 But the priests the Levites, the sons of Zadok, that kept the charge of my sanctuary when the children of Israel went astray from me, they shall come near to me to minister unto me, and they shall stand before me to offer unto me the fat and the blood, saith the Lord GOD:
Ezekiel 48:11 It shall be for the priests that are sanctified of the sons of Zadok; which have kept my charge, which went not astray when the children of Israel went astray, as the Levites went astray.
Ezekiel 40-48 deals with the glory of the future kingdom that Israel will enjoy once the nation is reborn (chapter 37) and her enemies defeated (chapters 38-39) at the second coming of Jesus Christ. Twice it is repeated that the sons of Zadok will enjoy special blessings and special privileges in that kingdom because they remained faithful to God despite the apostasy and idolatry of the nation.
Zadok was a priest who lived and served during the reigns of David and Solomon. He was of the line of Eleazer, Aaron's son (as opposed to the line of Ithamar; 1 Chronicles 24:3) and became the fulfillment of God's judgment upon the house of Eli (1 Samuel 2:35) at the outset of Solomon's reign over Israel (1 Kings 2:27, 35). As a young man, the Bible says that Zadok was mighty of valor (1 Chronicles 12:28). He remained true to the Lord and the king when others were carried away by the rebellions under Absalom (2 Samuel 15) and Adonijah (1 Kings 1). His progeny served faithfully in Judah's great revival under King Hezekiah (2 Chronicles 31). Because of this steadfast commitment, the Lord will richly reward Zadok and his sons when Jesus Christ returns to rule and reign on the earth.
There's an important practical lesson for us to learn from this interesting statement in the book of Ezekiel. Just like Zadok and his sons, we find ourselves in a time when God's people on a massive scale are going astray. Despite the apostasy and the apathy and the ignorance and the lukewarm condition of today's church, God calls on us to stand fast, be faithful, and remain true to the charge He's given us. And there are ETERNAL blessings and privileges that await those who will answer the call.
Allow me to correct a common misconception. The Bible clearly teaches us that (1) all saved people will live forever in heaven (2) and heaven will be a wonderful place (3) where we'll all have a new, glorified body (Philippians 3:20-21; 1 John 3:1-3) (4) and will be forever delivered from the very presence of sin.
What the Bible never teaches is that everything will be equal for everybody in heaven. There are rewards God has promised to those who serve Him faithfully! There are crowns to be won; there is gold, silver, and precious stones to be gained; there are positions in Christ's kingdom to be filled. God wouldn't have told us about all those things and held all that out to us if it didn't matter. Fact is, it will matter, and it will matter for all eternity! God will make it worth your while THERE to obey and stand and serve and give Him all you've got while you're HERE.
Now, for the sake of those who would over correct and swerve off into the ditch on the other side of the road, the Bible also never says anything to even indicate that if you don't serve God while you're HERE He'll beat you or send you to purgatory or make you sit in a corner for 1,000 years when you get THERE.
But you might just miss out on some special blessing like the one He has reserved for the sons of Zadok.
1 Corinthians 3:15 If any man's work shall be burned, he shall suffer loss: but he himself shall be saved; yet so as by fire.