How to share the same context between commands in Command-Pattern with C#?

I've implemented the command pattern (in a multi-support way) in my application.

Structure:

class MultiCommand : BaseCommand

abstract class BaseCommand : ICommand

Process Flow:

   var commandsGroup = new MultiCommand(new List<ICommand>()
            {
                new Command1(),
                new Command2(),
                new Command3(),
            });

   commandsGroup.Execute()

Now, suppose that in Command1 a somethingID is changed and I'll use this new value in Command2... And also, that there are plenty of other properties and objects that are being affected during the whole execution process.

How can I have a shared context for all Commands of the group?