As Nehemiah recounts in his prayer to God, these saviors were people like Gideon, Samson, Ehud, Joshua, and Moses. God gave them leaders that He inspired to deliver Israel from the terrible circumstance they were in.
Now put this verse—and the thought found in Obadiah 21 into a Millennial setting and our responsibilities as kings and priests—into the concepts of saving, judging, and teaching, all of which are involved in what God will be doing then. Remember also that God prophesies that Israel will go into captivity at the beginning of the Tribulation. They will be scattered all over the world in slavery, but God will regather them and bring them back to Israel, weeping, in a repentant state. Then what happens? Who will be their saviors, their deliverers? Who will judge them? Who will teach them?
Of course, all praise, honor, and glory for these things goes to God. But why—for what reason—is He preparing us? He is not going to do it all Himself. He will follow the patterns He established in the past, only this time He will accomplish His purposes with servants who are greater than Joshua, Gideon, Samson, Ehud—greater even than John the Baptist! He will work through saviors, judges, teachers—king-priests who are just like Him. Indeed, they will be His sons!