The pattern in the Bible:
Jonah 3 days and nights in the belly of the fish then 40 days to witness to Nineveh which did repent and turn from their wickedness to God.
Jesus to the people Israel during His days on earth said:
Jesus hung on the cross for 3 hours in total darkness from 12pm to 3pm and then there was an earthquake and when He was buried He was 3 days and nights in the heart of the earth after His crucifixion and then raised to life again for guess how long? 40 days then he ascended back to Heaven.
Also Moses before leaving the slave masters of Egypt was warned of God to post the blood of the innocent lamb on their door posts and there was darkness; guess how long? you got it 3 days. Then how long did they wander in the wilderness? yes 40 years.