A Frustrated Religious Apologist

A religious apologist says...

"Those who only critique and offer no alternative have a weak argument. If one is to critique, presumably s/he holds an alternate perspective that makes sense to them and they ought to be willing to subject such to the scrutiny of others. If not--then why? One leaves the impression that their counter philosophy is indefensible."

I’m guessing this apologist is becoming frustrated at having his arguments demolished whilst having nothing to aim at in retaliation.  He is essentially using the fallacious Argument from Ignorance

The statement that "Those who only critique and offer no alternative have a weak argument" is factually incorrect because those who offer no alternative are not actually presenting any kind of argument, therefore they do not have a weak argument. But the point is that if person A has an argument that is fallacious or weak according to person B - and person B has no alternative argument - the argument from person A is still fallacious or weak. 

For example, a creationist might argue that life is a result of divine intervention. A non-Creationist could provide several objections to this argument, even though he or she has no alternative explanation. But this lack of an alternative explanation does not make the creationist's argument more credible.

Or, imagine a conversation 10,000 years ago where person A states that thunder is created by a god called Thor. Person B finds this unbelievable but has no alternative explanation for the existence of thunder. However, this lack of an alternative does nothing to strengthen the argument that Thor creates thunder.