। ॥ ४२ ॥
In plain words
"But a son secures you a good destination." That argument too, once you press it, mostly falls apart. So this is what it comes to: wearing the body out with hardship, the deluded are earnestly praying for pain.
Close to the Sanskrit
If [it be said] "from a son there is a good destination" — that too, for the most part, is unable to withstand reasoning. Thus, through bodily hardships, suffering is earnestly begged for by the deluded.