1)
Why did they say Shalom, and he answered Shalom?
1.
Radak (4): They feared that Shmuel came [to rebuke someone] for a great sin. He answered that he did not.
2.
Malbim (4, 5): They feared that Shmuel came to bring Eglah Arufah. He answered that he did not.
2)
What is the meaning of "Hiskadeshu"?
1.
Radak citing Targum Yonasan: Prepare yourselves This is like "va'Ykadesh" (Shemos 19:14).
3)
Did he single out Yishai?
1.
Malbim: No. He was amidst the invitees, so people should not realize [that he will anoint one of his sons to be king].
