For it came to pass, when the flame went up towards heaven
from off the altar
That is, from the rock, which served instead of an altar, and from whence perhaps the fire sprung which consumed both the burnt offering and the meat offering, the flame of which went up to heaven; this rock or altar having no covering, but was "sub dio", open to the heavens:
that the angel of the Lord ascended in the flame of the altar;
making use of the smoke, as Josephus F18 says, as a vehicle in which he openly went up to heaven:
and Manoah and his wife looked on it;
on the flame and smoke, and the angel in it as he ascended; just as the disciples of Christ looked steadfastly on him as he went up to heaven, when a cloud received him out of their sight, ( Acts 1:9 Acts 1:10 )
and fell on their faces to the ground;
with astonishment and surprise at what they saw, through fear and reverence of the divine Being, of whose presence they were now sensible, and as worshipping of him, and praying to him.