Tafsir of Al-Ma'idah 5:21

يا قوم ادخلوا اﻻرض المقدسة

"O my people! Enter the Holy Land, Allah states that Musa encouraged the Children of Israel to perform Jihad and enter Jerusalem, which was under their control during the time of their father Yaqub. Yaqub and his children later moved with his children and household to Egypt during the time of Prophet Yusuf. His offspring remained in Egypt until their exodus with Musa. They found a mighty, strong people in Jerusalem who had previously taken it over. Musa, Allah's Messenger, ordered the Children of Israel to enter Jerusalem and fight their enemy, and he promised them victory and triumph over the mighty people if they did so. They declined, rebelled and defied his order and were punished for forty years by being lost, wandering in the land uncertain of where they should go. This was their punishment for defying Allah's command. Allah said that Musa ordered them to enter the Holy Land,

التي كتب الله لكم

which Allah has assigned to you meaning, which Allah has promised to you by the words of your father Israil, that it is the inheritance of those among you who believe.

وﻻ ترتدوا على أدباركم

and turn not back in flight from Jihad.

فتنقلبوا خاسرين

قالوا يا موسى إن فيها قوما جبارين وإنا لن ندخلها حتى يخرجوا منها فٳن يخرجوا منها فٳنا داخلون