John Gill Commentary Nehemiah 9:33

"Howbeit thou art just in all that is come upon us; for thou hast dealt truly, but we have done wickedly;" — Nehemiah 9:33 (ASV)

Howbeit, you are just in all that is brought upon us
They own the justice of God, could not complain of any wrong done them; and had he shown them no mercy at all, it was but what they deserved:

for you have done right, but we have done wickedly ;
he had done according to the truth of his word of promise, he had faithfully kept it, but they had transgressed his righteous law.