And he said to me, My grace is sufficient for thee, for my power is made fully perfect in weakness. More gladly therefore I will boast in my weaknesses, so that the power of the Christ may reside in me.

Forty days

And Moses entered into the midst of the cloud, and went up onto the mount. And Moses was on the mount forty days and forty nights.

And he was there with LORD forty days and forty nights. He neither ate bread, nor drank water, and he wrote upon the tablets the words of the covenant, the ten commandments.

When I was gone up onto the mount to receive the tablets of stone, even the tablets of the covenant which LORD made with you, then I abode on the mount forty days and forty nights. I neither ate bread nor drank water.

And having fasted forty days and forty nights, afterward he was hungry.

And he was there in the wilderness forty days tempted by Satan. And he was with the wild beasts. And the heavenly agents served him.

being tempted forty days by the devil. And he ate nothing in those days, and when they were ended, afterward he was hungry.

Horeb

Now Moses was keeping the flock of Jethro his father-in-law, the priest of Midian. And he led the flock to the back of the wilderness, and came to the mountain of God, to Horeb.

And mount Sinai, the whole of it, smoked, because LORD descended upon it in fire, and the smoke of it ascended as the smoke of a furnace. And the whole mount quaked greatly.

Remember ye the law of Moses my servant, which I commanded to him in Horeb for all Israel, even statutes and ordinances.

General references

And Jethro, Moses' father-in-law, came with his sons and his wife to Moses into the wilderness where he was encamped, at the mount of God.