Reading Matthew 12:26
If Satan drives out Satan, he is divided against himself. How then can his kingdom stand?
I cant seem to pin point where is his kingdom? Evil men dont seem to be united?
I see three questions plus the question in the quote.
I cant seem to pin point where is his kingdom? Opposing the spirit is the Flesh (Gal 5:17) Therefore when serving the Flesh we also serve Satan. "..you are slaves of the one you obey.." (Romans 6:14-19).
These two questions work together.
Singular: If a man hates himself and actively pursues damage to himself. How can he stay alive?
Married Couple: If the couple actively pursue damage to the relationship. How can the relationship survive?
Let's take a long look at the Scriptures around your referenced Scripture:
Matthew 12:25 through 28 KJV
and see if Jesus was actually saying that Satan had a Kingdom to begin with. What Jesus was retorting to was the verse preceding this retort (Matthew 12:24):
But when the Pharisees heard it, they said, This fellow doth not cast out devils, but by Beelzebub the prince of the devils.
Jesus was incensed by their claim that he was getting his power to do these miracles from Satan, and his angry retort was meant to marginalize them.
In verses 26 and 27 He is belittling them by:
The last stone he casts is in verse 28 where he tells them knowing what I have just told you my power must come from another source. and if my source is God then you have just seen the Kingdom of God.
Here are some other Scriptures concerning Satan's supposed power which you may find will help you in understanding Satan. Please remember that Jesus himself said that Satan was a liar and the father of lies.
Matthew 4:1-11 KJV
Mark 3:22-26 KJV
In This Scripture what Jesus is pointing to is that if what they were claiming were true then Satan does not have the power of God since he could not do what they claimed and be eternal.
Revelation 2:13 KJV
Revelation 12:9-12 KJV
Revelation 3:9 KJV
Revelation 12:9-12 KJV
This question is about spiritual world. How it is reflected within humanity? How it manifests? How a spiritual world stands?
To understand how a man can become evil man, or a good man, I will quote from Holy Tradition of Orthodoxy, where many mysteries about humanity and God where revealed to us through Holy Spirit and His servants. (http://tzarlazar.tripod.com)
With this understanding we can pin point how the kingdom of Satan stands. As an example think about 2 men driven by the same evil spirit. They maybe want to hurt themselves or to kill each other, in appearance they are not united but in spirit they are the similar, exercising the same activity. They are bearers of the same evil spirit, and they potentially contaminate with the same spirit people around them which they contact to .. the hate, the greedy, the deprivation, the anger, the proud etc are manifestations of the same evil spirit. When you observe this around you and inside you, over and over, you can realize in which Kingdom you or people around you are living and how this Kingdom stands.