What does Nehemiah 9:29 mean?

“Nevertheless they were disobedient, and rebelled against you, cast your law behind their back, killed your prophets that testified against them to turn them again to you, and they committed awful blasphemies.

Therefore you delivered them into the hand of their adversaries, who distressed them. In the time of their trouble, when they cried to you, you heard from heaven; and according to your manifold mercies you gave them saviors who saved them out of the hands of their adversaries.

But after they had rest, they did evil again before you; therefore left you them in the hands of their enemies, so that they had the dominion over them; yet when they returned, and cried to you, you heard from heaven; and many times you delivered them according to your mercies,

Yet many years you put up with them, and testified against them by your Spirit through your prophets. Yet would they not give ear. Therefore you gave them into the hand of the peoples of the lands.

“Nevertheless in your manifold mercies you did not make a full end of them, nor forsake them; for you are a gracious and merciful God.

Now therefore, our God, the great, the mighty, and the awesome God, who keeps covenant and loving kindness, don’t let all the travail seem little before you, that has come on us, on our kings, on our princes, on our priests, on our prophets, on our fathers, and on all your people, since the time of the kings of Assyria to this day.