1)
What is the meaning of "va'Yshasa"?
1.
Rashi: He divided, and rejected them verbally.
2.
Radak, Malbim: He removed his men from Sha'ul. They wanted to kill Sha'ul, since David did not kill him.
3.
Radak citing Targum Yonasan: He appeased them.
2)
Why does it say "ba'Devarim", with a Patach under the Beis (which implies known words)?
1.
Radak: They are the words mentioned - he is Meshi'ach Hashem, and similar matters.
3)
Why does it say "ba'Derech", with a Patach under the Beis (which implies a known road)?