There were two half-shekel offerings: a one-time donation (for the building of the mishkan) and the annual half shekel (for korbanot) – building fund vs. operating budget.
Why was there an upper limit for the machatzit hashekel, why can’t a rich person give more?
Reish Lakish says that the Machatzit HaShekel counters the shekalim that Haman paid Achashverosh to be able to annihilate the Jews. Haman is long gone and no longer a threat. What metaphysical power is there in Haman’s shekalim – all he was doing was bribing Achashverosh! What is the deeper message?
Rich and poor stand before God equally; Hashem doesn’t judge us by our objective accomplishments, He judges us by how much of ourselves we have given to Him.
Delivered at the OU Israel Center, March 3rd, 2019, 26 Adar I 5779