What is the legal ruling for saying, "May Allah reward Islam on my behalf with goodness," and is the religion of "Islam" considered among those accountable who receive recompense, reward, and punishment?

It was reported that Umar ibn Abd al-Aziz and Imam Ahmad, upon hearing "May Allah reward you on behalf of Islam with good," would respond, "Rather, may Allah reward Islam on my behalf with good." Both phrases are correct. The first means asking Allah to reward him for what he has offered to Islam, as narrated from Sufyan al-Thawri. As for the second, its meaning is that the favor and grace belong to Islam over the Muslim, and that no matter what a person offers, he will not fulfill the right of the blessing of Islam, which is from Allah's chosen religion and His grace upon His servants.