Is that your argument?
Again, one has no personal knowledge of how Paisley ever chose to apportion his time.
What we do know is that the time he accorded to both aspects of his career was spent very effectively.
You appear to be plagued with a kind of zero-sum myopia. That is: if he was doing activity related to his ministry he could not possibly have been doing things politically at the same time -- and vice versa.
It may be that your perspective is simply jaded by all that "popular" talk about separation of church and state in the US, which at its core is only meant to effect separation of Biblical morality from political discourse.
From what I know of Paisley (and you might know too if you listened to any of his sermons, as I have already recommended to you twice before) it would be entirely fair to say that Paisley considered his participation in the political debates and processes of his time to be something he did both as the voice of Christian morality and as an extension of his ministry.
That said, most of us can walk and chew gum at the same time. Others, perhaps yourself included, are not able to do more than one thing well at a time. And that's OK. That's not necessarily a "bad" thing, per se, but it might be that this condition is impoverishing your perspective somewhat -- at least in this discussion.
So, did your priest say he'd provide at least some measure of absolution for you, if the two of you sat down and listed to Paisley's sermons together -- if for no other reason than learning how one who is both a theologian and a statesman might be able to hold forth so effectively and for so long on what he believes about issues in both contexts?
FReegards!