He was buried in the royal tombs in Jerusalem. This was because he had done so much good for the people of Israel, for God, and for the Temple.

Jehovah, the God of Israel says: 'I said indeed that your house and the house of your father should walk before me all the days of your life.' Now Jehovah says: Far be it from me. I will honor those who honor me. I will not regard those who think little of me.

David died and was buried in David's City.

After a six-year wait Jehoiada the priest decided that it was time to take action. He made a pact with five army officers: Azariah son of Jeroham, Ishmael son of Jehohanan, Azariah son of Obed, Maaseiah son of Adaiah, and Elishaphat son of Zichri.

This is what Hezekiah did throughout Judah. He did what was good and right and true to Jehovah his God.

Nehemiah's prayer: Keep me in mind, O my God, in connection with this, and do not let the good which I have done for the house of my God and its worship go from your memory completely.

Men and brothers let me freely speak to you about the patriarch David that he is dead and buried. His grave is with us to this day.

For God is not unrighteous (unjust) to forget your work and the love you showed for his name. You ministered to the holy ones and continue to minister.

Treasury of Scripture Knowledge

Summary

And they buried him in the city of David among the kings, because he had done good in Israel, both toward God, and toward his house.

Bible References

In the city

Jehovah, the God of Israel says: 'I said indeed that your house and the house of your father should walk before me all the days of your life.' Now Jehovah says: Far be it from me. I will honor those who honor me. I will not regard those who think little of me.
David died and was buried in David's City.
Men and brothers let me freely speak to you about the patriarch David that he is dead and buried. His grave is with us to this day.

Because

This is what Hezekiah did throughout Judah. He did what was good and right and true to Jehovah his God.
Nehemiah's prayer: Keep me in mind, O my God, in connection with this, and do not let the good which I have done for the house of my God and its worship go from your memory completely.
For God is not unrighteous (unjust) to forget your work and the love you showed for his name. You ministered to the holy ones and continue to minister.
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