Allah said,

﴿فَإِنَّهَا مُحَرَّمَةٌ عَلَيْهِمْ أَرْبَعِينَ سَنَةً يَتِيهُونَ فِى الاٌّرْضِ﴾

(Therefore it is forbidden to them for forty years; in distraction they will wander through the land.) When Musa supplicated against the Jews for refusing to fight in Jihad, Allah forbade them from entering the land for forty years. They wandered about lost in the land of At-Tih, unable to find their way out. During this time, tremendous miracles occurred, such as the clouds that shaded them and the manna and quails Allah sent down for them. Allah brought forth water springs from solid rock, and the other miracles that He aided Musa bin `Imran with. During this time, the Tawrah was revealed and the Law was established for the Children of Israel and the Tabernacle of the Covenant was erected.