«قلت ثقلت إذ أتيت مراراً»
I said: you have become burdensome by coming repeatedly.
«قال ثقلت كاهلي بالأيادي»
He replied: I have burdened your shoulders with acts of generosity.
The first speaker uses thaqilta as a complaint about troublesome visits. The respondent reuses it to signify the “weight” of benefits conferred. The phrase “with acts of generosity” fixes the new relation.
One expression is preserved, while its complement and rhetorical force change—an instance of the second kind of qawl bi-l-mūjib.