1)
What is the meaning of "va'Yikrav ha'Melech Al ha'Mizbe'ach"?
1.
Radak #1: Va'Yikrav is Po'el Yotzei (like v'Hikriv); he offered Korbanos on it 1 .
2.
Radak #2: It is Po'el Omed. It is as if it says El ha'Mizbe'ach (he himself came close to it).
1
According to this Perush, "va'Ya'al Alav" is connected to the next verse, and details what he offered - "Olaso
2)
Why did he himself offer?