I believe that his soul may be in danger.
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I wrote as follows:
Surely, you've been on this Earth long enough to realise that 'truth' is ephemeral.
First we had God. He was followed, after a 14,000,000,000 year-long gestation, by Jesus. He said, " ... I am the truth ..."
Many mortals came after.
Bishop Ussher declared that the world was created on 23rd. October, 4004 BC, (by the Julian calendar).
Darwin caused uproar.
Thomas Malthus said we should be extinct by now.
Richard Dawkins confounded everyone with 'intelligent design', while Noel Edmonds engaged in 'cosmic ordering'. (He needs it.)
NOW even the Pope confesses to fallibility! (We all knew that, anyway.)
The only absolute truth, according to nobody else but me, (in whom I have complete faith), is as follows:
If you wish to parenthesise a complete sentence, perhaps as an afterthought, the final full-stop belongs before the closing bracket.
See below:
(Otherwise, truth is nothing but myth, legend and superstition.)
It would silly like this: (Otherwise, truth is nothing but myth, legend and superstition).