You will tread on the lion and the adder; the young lion and the serpent you will trample underfoot.
Christ has called us and has tied us with a most pleasing bond to His vineyards, that is, to His spiritual gifts, with which He fills us, so that we fear none of all the things that can harm us. Would that we truly understood and impressed on our hearts the divine promises, namely, that our sins have been forgiven us, that death and the devil have been conquered, and that hell has been destroyed, as this is gloriously proclaimed in Psalm 91:13: "You will tread on the lion and the adder, the young lion and the serpent you will trample underfoot"! He who firmly believes this imbibes these promises, feeds most pleasantly on these vines, and is lord over death.
From Lectures on Genesis (Luther's Works 8:251)