On BBC Eastenders soap: why is it that the gang don't want to allow Jase to leave?

Is it because:
It a loss of face when a member leaves a gang
They are concerned he knows all their 'inside' secrets
The gang boss would see it as a loss of his control/authority
Some other reason?
Isn't there a saying that no one ever leaves the Mafia?

It is because The old man of the gang was wanting to hand it down to Jase as he was retiring from all the fighting crap, but Jase wanted out of it all, As Jase turned his back pon them now They want to kill him ( quite sad actually as he has a cuter litto boy, but oh well he shouldnt get involved in **** like that from the furst place LOL )

i think that it is all those reasons

Gang boss would see it as a loss of control they are supposed to be the eatenders mafia type thing and very nasty and yes noone leaves the mafia is a true saying.

loss of face, the fact he knows things about the others, people like that have a bond and a set a rules where you all stand together you do not break the bond

regards x kitti x

You've more or less covered every reason yourself! All of the things you have mentioned are linked to why they won't allow Jase to leave. I think the main one is that "it a loss of face when a member leaves a gang" because Tel(the gang boss) always wanted him from the start and therefore, wanted him to come back. However, Jase refused and like they always say: "nobody refuses to bosses."

The thing that I don't get though is that:

"Why are they about to enter the Vic?"

Is it because of the fact that they thought Jase was inside or because they wanted money...?

I don't get it...but then again, that's the whole point of it - you'll just have to wait and find out...

Its an un-written law that once you work for the Mob, Mafia, etc etc, that you can never leave, alive.
As you have said, he knows too much & as such is open to persuasion & bribary by the authorities to 'Spill the beans' as they say.

yes becasue he left the gang to go on the straight & narrow & be a good law abiding Walford citizen

The gang boss said tonight that they would lose face and look soft if they just let Jase go.

Vinz, they were about to enter the Vic, because in last nights episode, one of the gang members went in and saw Jase in there with Dawn, the guy then phoned the rest of the gang and told them where he was and to get down there, but in the meantime Jase went back to Dawns house so he wasn't in the Vic when the gang arrived.

i dont no about the saying but i think that is why and also terry (the boos of the gang) riased Jase as his own and know that jase just wants to get on with life Terry doesn't like that idea because of some reason it isnt all that clear but i think that it also why hope it helped lol