"God is not willing to do everything, and thus take away our free will and that share of glory which belongs to us"

The quote indicates that according to Machiavelli, God values our free will and the sense of duty and accomplishment that includes making our own options, even if that implies not intervening in every aspect of our lives. To put it simply, by giving us the flexibility to make our own choices, we have the opportunity to take credit for our successes and learn from our errors.