Exodus 10:21-23

Againe ye Lord said vnto Moses, Stretch out thine hand toward heauen, that there may be vpon the lande of Egypt darkenesse, euen darkenesse that may be felt. Then Moses stretched forth his hande towarde heauen, and there was a blacke darkenesse in all the land of Egypt three daies. No man saw an other, neither rose vp from ye place where he was for three dayes: but all the children of Israel had light where they dwelt.