One first hears of Joshua the son of Nun in Exodus 17:9 when Moses called upon him to engage in battle. The Lord mentions Joshua's name in Exodus 17:14. Moses calls Hoshea son of Nun by the name of Joshua in Numbers 13:16 and Deuteronomy 32:44. Moses recounts in Deuteronomy 3:28 that the Lord instructed him to "commission Joshua, and encourage and strengthen him, for he will lead this people across and will cause them to inherit the land that you will see." Joshua is recalled in Judges 2:7, 1 Kings 16:34, 1 Chronicles 7:27, Nehemiah 8:17, and in the New Testament in Acts 7:45 and Hebrews 4:8.

Joshua is a minor figure in the Torah, being one of the spies for Israel (Num 13-14) and in few passages as Moses's assistant. He is the central character in the Hebrew Book of Joshua. According to the books Exodus, Numbers and Joshua, he became the leader of the Israelite tribes after the death of Moses; his name was Hoshe'a the son of Nun, of the tribe of Ephraim, but Moses called him Yehoshu'a (Joshua) (Numbers 13:16) the name by which he is commonly known; and he was born in Egypt prior to the Exodus, and was probably the same age as Caleb, with whom he is occasionally associated.

He was one of the twelve spies of Israel sent by Moses to explore the land of Canaan. (Numbers 13:1-16) After the death of Moses, he led the Israelite tribes in the conquest of Canaan, and allocated the land to the tribes. According to Biblical chronology, Joshua lived between 1500–1390 BC, or sometime in the late Bronze Age. According to Joshua 24:29, Joshua died at the age of 110.