Most of the Christianity of the past was too passive; and the powers of strategic evil have long-since worked-out how to deal with it...
Subvert/ corrupt the authoritative leadership, peer groups and high status intellectual influences; do the same for the texts, the interpretations, the rituals and symbols, morals and ethics... all can-be/ has-been repurposed for evil.
Anybody whose Christianity is passive, here and now, in the modern West, is like a ticking time-lock: sooner-or-later the door will open, evil will get-in and take-over.
To be passive is to be defensive - you only need one error or lapse and you are done-for.
Being active clearly isn't a matter of action, of behaviour; since
most of he most active people are among the most passive. Evangelism - yes! But evangelism to what: when so much has been repurposed?
to a basic, inner and motivational stance. I can't see any way around the fact that it must be individually-rooted and based on a direct knowing - I just can't see how this implication can be avoided (despite all the obvious and real hazards). Personal destiny needs to be found, known explicitly, and lived-by.
In essence we need to step outside The System - and everything external, objective and social (including actual Churches) is (more or less, usually more) inside The System.
Only outside The System can we found solid ground to work from.
But what kind of work, when so much is subjected, and we are intending to be active and to support the activity of others?
Outside The System is not imaginary, subjective, unreal - but the opposite: direct, personal, universal reality. That's the place we need to work.
But what specifically to do for me, here, now?
Well, nobody can tell you - you must actively discover it. That's the first active step.