Why did the hittites and egyptians conclude a peace treaty in 1258 b. c.e.?

The treaty between the Hittites and the Egyptians has been concluded with the purpose of ending the 80 years long war between the two countries that was damaging both sides.

This treaty is one of the oldest treaties in the world, and is considered as a prime example of diplomacy in this period of time. The treaty itself has 20 points/obligations that are to respected from both sides, like for example:

- both countries being obligated to never attack one another till the end of time and to never try to occupy the territory of the other country...

- if there's a criminal or escaped prisoner that has crossed from one country to the other, that he/she should be exiled if the country requires that...

- both countries were obliged to help each other in a war with a third country...

congress also has implied powers, which derive from the necessary and proper clause of the constitution and permit congress "to make all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this constitution in the government of the united states.