I think using emotive terms like “told them lies” is stretching things a bit far.
I think we will have to differ in our assessment of how emotive my sentence was; I could have used a variety of terms, but the basic premise remains.
We tell many, many lies to children, some based around belief, some based around convention, some based around social cohesion, but they remain lies.
The crux of my question seems to have slipped under your radar; this is the important bit:
will they continue to believe
I suspect most grown ups really, actually, truthfully don’t believe the religious explanation, so using it is a way of putting off an awkward and emotionally difficult conversation. Not much wrong with that, but I think being open and honest is a far better way of approaching things.