What is the meaning of "v'Tzalchu ha'Yarden"?
Rashi: They split the Yarden [with their shields]. Radak - this is like "Pen Yitzlach ka'Esh Beis Yosef" (Amos 5:6). The Targum of "va'Yvaka Atzei Olah" (Bereishis 22:3) is v'Tzalach. I.e. they crossed by foot; there was a place at that time 1 where one may cross by foot. Ralbag - it seemed that they split it, because so many passed.
Radak: They crossed the Yarden. Also Yonason translates v'Gazu, similar to his translation of (Yehoshua 2:7) "ha'Mabros", i.e. Megizasa (places to cross the river).
E.g. in Tishrei rivers are shallow, after a whole summer without rain. However, it was still deep enough for a ferry to pass through (verse 19). (PF)
What is the meaning of "Lifnei ha'Melech"?
Radak: To come in front of the king.
Kli Yakar: They showed him the shallowest place for he and his officers to walk across.
Malbim: After Yehudah and Binyamin had come to greet David on the eastern side, Yehudah split the Yarden (crossed back to the west, before the king did).
