"and deliver us from evil"

From John Calvin's commentary on Mark 9:14-27:

. . . we learn how many ways Satan has to harm us unless he is held off by God's hand. All the weaknesses of the flesh and soul, which we feel to be innumerable, supply him with darts to wound us. Therefore we are more than stupid if our wretched state does not move us to pray. But the incomparable goodness of God shows itself in the way that, although we are exposed to so many different evils, yet He guards us by His help--especially if we consider how fiercely our enemy burns to destroy us. But there ought to come to our minds this comfort, that Christ came to bridle his raging, and that we remain safe among so many perils because the heavenly medicine is greater than our ills.