Ten thousand talents is about equal to 33 tons of gold or more than a billion dollars.
One hundred denarii is about one hundred days of work at minimum pay.

Peter’s confession is the rock upon which Christ will build his church. Notice the Greek ” will be having been” bound in heaven, which means that which is already done in heaven counts in building His church.
This last phrase probably refers to the Transfiguration occurring six days later. (Next chapter)
“Everyone knows that only God” can forgive sins.
In those days, a bed was only a mat, less than half an inch thick.
Tax collectors were despised, having colluded with the Romans to collect sometimes much more than required by Roman law. Corruption was rampant.
Luke and John also record this call.