'Forty' represents completeness because 'four' and 'ten' both mean what is complete. Forty is the product of four and ten. Compound numbers have a meaning similar to the simple numbers which compose them, and all numbers in the Word represent spiritual realities.

(Odkazy: Arcana Coelestia 9437; Exodus 24:18)

9437. 'And Moses was in the mountain forty days and forty nights' means the instructions given and influx in their completeness. This is clear from the meaning of 'forty' as completeness. 'Forty' means completeness because 'four' means that which is complete, 9103, as similarly does 'ten', 3107, 4638, and forty is the product of four multiplied by ten. For compound numbers have a meaning similar to the simple numbers of which they are the product, 5291, 5335, 5708, 7973; and all numbers in the Word mean spiritual realities, see 575, 3252, 4264, 4495, 4670, 5265, 6175. All this goes to explain why Moses was in the mountain forty days and forty nights. The fact that 'forty' here means the instructions given and the influx in their completeness is evident from Chapters 25-32 which come next, recording the instructions Moses received, that is, instructions regarding the ark, Aaron, the urim and thummim, and sacrifices. The reason why influx in its completeness is also meant is that at that time Moses began to represent the outward holiness of the Word, which acted as the intermediary between the Lord and the people, and mediation is accomplished by means of influx through that holiness into the representative existing among that people, 9419.

[2] It was because 'forty' represented completeness that Moses remained on Mount Sinai forty days and forty nights not only this time but also on another occasion, Exodus 34:28; Deuteronomy 9:18, 25; 10:10. For the same reason the children of Israel wandered in the wilderness forty years until, as it says in Numbers 14:33-34; 32:13, all that generation had been consumed; Jonah told the Ninevites that their city would be overturned after forty days, Jonah 3:4; the prophet was commanded to lie on his right side and bear the iniquity of the house of Judah forty days, Ezekiel 4:6; it says regarding Egypt that it would be made completely desolate for forty years, after which they would be gathered from the peoples, Ezekiel 29:11-13; and the earth was rained on forty days and forty nights, so that it was inundated with the flood, Genesis 7:4, 12, 17. From all this it is evident why the wicked person was to receive forty blows, Deuteronomy 25:3, for 'forty blows' meant the punishment in its completeness. It is also evident what should be understood in the prophecy of Deborah and Barak when it says that no shield or spear was seen among the forty thousand of Israel, Judges 5:8, 'among the forty thousand of Israel' meaning among them all. It is in addition evident why the temple built by Solomon was forty cubits long, 1 Kings 6:17, as was the new temple, according to Ezekiel 41:2; for in the highest sense 'the temple' means the Lord, and in the internal sense heaven and the Church, so that 'forty' means completeness in respect of representation. And it has a like meaning in other places.