What is "Yamim v'Arba'ah Chodoshim"?
Radak, Targum Yonasan: It was four months and some days from the fifth month.
Malbim: He was some days in Gas, and four months in Tziklag. This is why days are mentioned before months.
Pesikta Zutresa (Bamidbar 129b) says that Idan is a year.
Rashi: This cannot be! David came to Gas after Shmuel died; Sha'ul ruled only four months after Shmuel died (Seder Olam)! Also, Eli was Shofet for 40 years, and the Aron [was captured, the day he died, and] was in Kiryas Ye'arim for 20 years. These 60 years include 52 years of Shmuel's life; Chanah's pregnancy and these four months comprise one more year, and David reigned in Chevron for seven years before bringing the Aron from Kiryas Ye'arim. This shows that Sha'ul ruled only four months after Shmuel died [i.e. 40+20= 52+1+7. We must add to the 40 and 20, seven months during which the Aron was in Sedei Pelishtim (6:1)! We must say that some numbers of years are rounded off. The extra or missing months account for the seven extra months. According to Targum Yonasan, the pregnancy and David's time in Gas comprise two years. We can say that extra or missing months account for the five missing months! - PF) Radak - Shmuel died seven months before Sha'ul died. Also, Sha'ul ruled only two years. You cannot say that [from when he became king, including] everything that happened with David (Sha'ul took him to play for him, he killed Galyus, and all the times he fled Sha'ul, until he returned to Achish) was within eight months!
