A woman who was a member of Gerald Flurry's personalty cult, the Philadelphia Church of God, relates what she had her family experience in her  22 year membership in the PCG.
She writes what everyone who has been part of Armstrongism has experienced.
When you first come in, it looks so good--lots of friends, laws to 
live by that seem to promise happiness. All is well--until they think 
you didn't do something they said to do. Then you're constantly watched 
as they can't take the chance of you thinking for yourself and breaking 
rank. Just the smallest thing is suspicious. Then comes the threats. You
 can't be part of this if you don't follow suit. They begin to instill 
fear. After that you're hooked. But you keep going on and on because all
 your friends are there, all your money goes there, and your children 
are in there.
They have cut you off from the world ever so gradually and 
replaced everything and everybody with them only. The constant fear of 
being put out and not "making it into God's Kingdom" keeps you from 
leaving. You will do anything. Your  hope of a lifeline to someone on 
the outside, to get out, is gone. You have alienated everyone in your 
family that could help you to get out. You're constantly talking about  
prophecies and that "we alone" are called and going to the "place of 
safety" and that no one understands but us in the "true church." It 
really turns others off.  Giving the Reigns of Our Life Over to Someone Else
Fear is the only way the leaders of all the Armstrongite splinter groups stay in power.  By threatening a member with the lake of fire and eternal damnation for going against them, it scares people enough to keep them submissive and weak. 
Cultwatch says this about fear:
Cult leadership is feared. To disagree 
with leadership is the same as disagreeing with God. The cult leaders 
will claim to have direct authority from God to control almost all 
aspects of your life. If the cult is not a religious group then 
questioning the leaders or program will still be seen as a sign of 
rebellion and stupidity.
Guilt will be 
used to control you. Maybe the reason you’re not making money is because
 you’re not “with the programme”. Maybe the reason you’re not able to 
convert new recruits is because “your heart is prideful and full of 
sin”. It could never be that the programme isn’t working, or those new 
recruits have valid reasons for not joining. It’s always your fault, you
 are always wrong, and so you must try harder! You will also be made to 
feel very guilty for disobeying any of the cult’s written or unwritten 
rules.
 Psychology Today writes:
.....pathologically narcissistic. They all have or had an over-abundant 
belief that they were special, that they and they alone had the answers 
to problems, and that they had to be revered. They demanded perfect 
loyalty from followers, they overvalued themselves and devalued those 
around them, they were intolerant of criticism, and above all they did 
not like being questioned or challenged. And yet, in spite of these less
 than charming traits, they had no trouble attracting those who were 
willing to overlook these features. 
"Pathologically narcissistic" is a great description of the leadership of almost all the Church of God's.  One needs to look no further than David C Pack and Gerald Flurry to see these traits blatantly obvious. 
On a Facebook page recently, a person wrote that they witnessed a scene with David C Pack that left them appalled.  It seems a group of young men and women were standing around waiting for Dave to arrive.  When he did, the guys rushed to see who got to open Dave's car door first as they shoved the women aside.  
Demanding extreme loyalty is the only way these men stay in power.