John Calvin Commentary Luke 10:19

"Behold, I have given you authority to tread upon serpents and scorpions, and over all the power of the enemy: and nothing shall in any wise hurt you." — Luke 10:19 (ASV)

Lo, I give you power. This is said by way of admission. Christ does not affirm that the gift of which they now boast is not illustrious, but reminds them that they ought to keep their eye chiefly on something loftier still, and not remain satisfied with outward miracles.

He does not altogether condemn their joy, as if it were groundless, but shows it to be faulty in this respect: that they were immoderately delighted with a temporal favor and did not elevate their minds higher.

To this disease, even the godly are almost all liable. Though the goodness of God is received by them with gratitude, yet the acts of divine kindness do not assist them as they ought, by becoming ladders for ascending to heaven.

This makes it necessary that the Lord should, as it were, stretch out His hand to raise them up, so that they may not rest satisfied with the earth, but may aspire to heavenly renovation.

The power of the enemy is the name given by Him to every kind of harm, for everything that is hostile to us is wielded against us by Satan.

I do not mean that everything that tends to injure people is placed at his disposal; but that, being armed with the curse of God, he endeavors to turn all His chastisements to our destruction, and seizes them as weapons for the purpose of wounding us.