Why is 3 am considered the "witching hour" or the 'devil's hour'?
Before I begin theology time I want to start with story time. When I was 16 I had a dream that black, clawlike hands were messing with my alarm clock and giggling. As soon as the dream ended my alarm clock went off at 3AM! That experience was more frightening than any horror movie you could ever watch and it took quite a while before I had a good nights sleep after that experience. I assure the reader that my alarm was always set for 6AM and that I have no idea how it could have been changed. I questioned anyone who could have been in my room and everyone swore they did nothing to my alarm clock. Only conclusion I have ever come to is spiritual warfare.
Now it's theology time. There is nothing in the Bible that says 3 AM is the Devil's hour. Some people believe that Jesus rose from the dead at 3 PM and the Devil likes to work at the opposite hour. The Bible only says Jesus rose from the dead on the third day it does not say what time he rose. As far as we know Jesus rose from the dead at 3 AM! The reason people say Jesus rose from the dead at 3 PM is because it is picturesque. It's the brightest time of day so it represents the truimph of good over evil. But there is nothing in the scripture that requires we believe Jesus rose at 3PM.
So we can't associate Satan with a certain time but can we associate him with darkness? Absolutely.
Ephesians 6:12 " For we do not wrestle against flesh and blood, but against the rulers, against the authorities, against the cosmic powers over this present darkness, against the spiritual forces of evil in the heavenly places."
It is fair to say that Satan is the leader of these evil cosmic forces of darkness. However, there is no reason to believe that "darkness" refers to literal light and dark. Instead, darkness refers to lack of good, lack of wisdom, lack of truth, and lack of beauty. I think reading that Satan is mostly active at night is stretching the scripture. Satan wants to tempt us. How can he do this when we are asleep?
I do think that Satan does use night to his advantage. Satan works through fear. People are more easy to scare when it's dark and if you want to harass someone you mess with their sleep. I don't think the Devil owns 3AM but I do think he uses it when he can. It's even better for him if people believe he owns the night; makes him more scary.
Truth is Satan has nothing; not even 3AM. He is Lord of the Flies not Lord of the Night. As Christians we need to pray more so that we will experience victory over the Devil. "Some things can only come out with prayer and fasting". As Christians we can take the night back too. Don't let the Devil have 3AM.