Egyptian Spears were used since the earliest times for hunting. While they were used as javelins to catch fish they were later replaced by the bow and arrow. It continued to be used as a lance for hunting bigger animals such as elephants and wildebeests as they had a much longer reach than most weapons.

In war, it did not gain the same degree of importance as it did in classical Greece. It was, though, considered important enough to be depicted in the hands of Ramses II in a painting. It must be noted however that in the painting Ramses was not shown to be in a war-like or belligerent stance but in more of an exultant one.

During the New Kingdom, it was often an auxiliary weapon of the charioteers, who were thus not left unarmed after spending all their arrows. It was also most useful in their hands when they chased down fleeing enemies stabbing them in their backs. Amenhotep II’s victory at Shemesh-Edom in Canaan is described at Karnak

…… Behold His Majesty was armed with his weapons, and His Majesty fought like Set in his hour. They gave way when His Majesty looked at one of them, and they fled. His majesty took all their goods himself, with his spear…..

W.M.Flinders Petrie A History of Egypt, Part Two, p.155

Egyptians eventually began adopting weapons and tactics prevalent among the other Mediterranean nations; in the war between Cyrus and Croesus huge numbers of Egyptian spearmen were involved

… a body of Egyptians was coming by sea, amounting–so said the Indians–to 120,000 men, armed with long shields reaching to their feet, huge Egyptian Spears (such as they carry to this day), and sabers.

Xenophon: Cyropaedia, Translated by H. G. Dakyns

According to Xenophon, they fought in squares one hundred men wide and one hundred deep.

Their Egyptian Spears were immensely stout and long, such as they carry to this day, and the huge shield not only gave more protection than corslet and buckler but aided the thrust of the fighter, slung as it was from the shoulder. Shield locked into a shield, they thrust their way forward; and the Persians could not drive them back, with their light bucklers borne on the forearm only.

Xenophon: Cyropaedia, Translated by H. G. Dakyns

Hence it is safe to conclude that while spears were very prevalent in Ancient Egypt as hunting tools their lack of use as weapons caused them to slowly die out. Over a period of time, they became more like props in the hands of guards than an actual weapon of battle.