'Slips' in the Bible

as when a man goes into the forest with his friend to cut wood, and his hand swings the axe to cut down the tree, and the iron head slips off the handle and strikes his friend so that he dies—he may flee to one of these cities and live;

I will get revenge and pay them back at the time their foot slips; for the day of their disaster is near, and the impending judgment is rushing upon them!"