Psalm 60: God rejects and saves

You have rejected us, God, and burst upon us;
you have been angry—now restore us! You have shaken the land and torn it open;
mend its fractures, for it is quaking. You have shown your people desperate times;
you have given us wine that makes us stagger. But for those who fear you, you have raised a banner
to be unfurled against the bow. Save us and help us with your right hand,
that those you love may be delivered. Is it not you, God, you who have now rejected us
and no longer go out with our armies? Give us aid against the enemy,
for human help is worthless. With God we will gain the victory,
and he will trample down our enemies. (Psalm 60:1-5, 10-12 NIV)

I have a hard time understanding the psalms and this view that God constantly rebukes and then saves. I am handful that I am not under the law but under grace. But Lord you are sovereign and I don't understand what that means for how you interact with your world and all that happens here good or bad. Please Lord teach me.
Amen