1)
Is this a statement or a prayer?
1.
Malbim (Shmuel II, 7:24): It is a statement that begins a prayer. Yisrael is special among the nations, and you made Beis David special in Yisrael. Just like You made Yisrael special among the nations forever, may You establish Beis David forever! 1
1
Shmuel II, 7:24 is the same as our verse, just it says "va'Techonen Lecha" in place of "va'Titen." (PF)
2)
Why is David extolling the praises of Hashem and Yisrael?
1.
'Rashi': Because You are unique in Your world, and Your nation is the most special, it is proper that You give to them a great, proper king.
