1 Chronicles 22:1

Overview - 1 Chronicles 22
David, foreknowing the place of the temple, prepares abundance for the building of it.
He instructs Solomon in God's promises, and his duty in building the temple.
17 He charges the princes to assist his son.
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1 Chronicles 22:1  (King James Version)
Then David said, This is the house of the LORD God, and this is the altar of the burnt offering for Israel.

This is the house
David perhaps had some assurance that this was the place on which God designed that His house should be built; and perhaps it was this that induced him to buy not only the threshing-floor, but probably some adjacent ground also, as Calmet supposes, that there might be sufficient room for such a structure.
21:18-28 Genesis 28:17 ; Deuteronomy 12:5-7 Deuteronomy 12:11 ; 2 Samuel 24:18 ; 2 Chronicles 3:1 ; 2 Chronicles 6:5 2 Chronicles 6:6
Psalms 78:60 Psalms 78:67-69 ; Psalms 132:13 Psalms 132:14 John 4:20-22

and this is the altar
2 Kings 18:22 ; 2 Chronicles 32:12