Verse 17
On a certain day - This was when he was at Capernaum. See Mar 2:1.
The power of the Lord - Δυναμις Κυριου The mighty or miraculous power of the Lord, i.e. of Jesus, was there to heal them - as many as were diseased either in body or soul. Where the teaching of Christ is, there also is the power of Christ to redeem and save.