Isaac L

The Spirit coming upon the 70 Elders enables them to lead. The temporary manifestation was that they prophesied. Moses longed for the people to have this experience because they seemed to only know God secondhand - through Moses. They lacked this direct, personal encounter with God.

In the OT, the primary purpose seems to be: to select, confirm and equip the individual for a certain office or task, usually quite an extraordinary one. In some cases the effect of the Spirit coming upon the person is to make him closer to God; on some cases, he prophesies, or exerts extraordinary strength and bravery in battle.