At the start of Parshat Beshallach, we read, "The Children of Israel were armed when they went up from Egypt." (Exodus 13:18) The Hebrew term for armed is "chamushim". We learn many reasons for this particular word. Rav Yaakov Kamenetzky said they were armed with the "chamishei chumshei Torah" (the five books of the Torah. Rashi tells us that the word "chamushim" comes from the word for five, and that only one-fifth of the Jewish people left Egypt. The others were too assimilated to give up their Egyptian lives, and so as they demanded to live like Egyptians, they also died like Egyptians.
All these interpretations of "chamushim" are great, but what about the plain text...?
The children of Israel were armed, and right afterwards it says (Exodus 17:19), "Moses took the bones of Joseph with him."
Yosef, the only one in the Tanach that is called hatzaddik (the righteous one); Yosef who with the help of G-d interpreted dreams; Yosef who with the help of G-d saved the world from starvation. Moshe took this incredible Yosef's bones and don't you think that that alone was enough to safeguard the people?
Don't you think that the vow that the Jewish people made to take Yosef's bones with them and bury them in Eretz Yisrael was enough to safeguard Am Yisrael?