What is the legal ruling on using the verse "He said, 'Yes, but to reassure my heart'" to emphasize something?

There is no harm in adducing a Qur'anic verse to substantiate a meaning similar to the one for which it was originally revealed. This falls under the category of quotation and inclusion (tadmeen). Ibn 'Aqil mentioned that there is no objection to including Qur'anic verses for purposes that are analogous to the original intent of the Qur'an, as it enhances the discourse.