And he arose, and did eat and drink
Of what was left of the cake and cruse of water, before provided for him:
and went in the strength of that meat forty days and forty nights
unto Horeb the mount of God;
for so long he was going to that place, though it might have been gone in three or four days; but he went in byways, and wandered about in the wilderness, as the Israelites did, and that for the space of forty days, as they did near forty years; and all this while he had no other sustenance than what he had taken under the juniper tree, from whence he set out, which must be supernatural; for it is said F20, a man cannot live without food beyond seven days, (See Gill on Exodus 24:18) the food either staying in his stomach all this while, or however the nutritive virtue of it, by which he was supported, and held out till he came to Horeb or Sinai; called the mount of the Lord, because here he had appeared to Moses in the bush, and from hence gave the law to the children of Israel. Abarbinel is of opinion that this term of forty days was consumed in his whole journey to Horeb, his stay there, and return to the land of Israel.
The Brenton translation of the Septuagint is in the public domain.