Matthew 9:5
For which is easier, to say, Your sins are forgiven, or to say, Rise and walk? The rhetorical question distinguishes the verifiable from the unverifiable: saying your sins are forgiven is not empirically demonstrable, while saying rise and walk is immediately testable. The harder command (rise and walk) will demonstrate the authority behind the easier command (your sins are forgiven). The physical healing is the public proof of the spiritual reality — if Jesus can heal the unhealable body, it is not a stretch to believe he can forgive the unforgivable sin. The logic is from the harder-to-demonstrate to the easier-to-demonstrate.