'De grote schare' doesn't exist anymore. It is 'de grote menigte' now in Rev.7:9
and also 'geloof oefenen' was something that had been literally translated from English, not from Greek. In Greek 'faith' can be a verb, just like in Dutch. In English it needs other words...to put faith in someone, have faith, exercise faith.
Indeed we had lots of times spelled out in talks how we have to EXERCISE faith...as if it is a work we have to do. (Exercising like in 'workout, training'). All based on that translation from ENGLISH instead of Greek... now it is simple 'geloven' instead of 'geloof oefenen'.