My father sought permission from the Prophet ﷺ. (When permission was granted and he came near him) he lifted his shirt, and began to kiss him and embrace him (out of love for him). He asked: Messenger of Allah, what is the thing which it is unlawful to refuse? He replied: Water. He again asked: Prophet of Allah, what is the thing which it is unlawful to refuse? He replied: Salt. He again asked: Prophet of Allah, what is the thing which it is unlawful to refuse? He said: To do good is better for you. (Using translation from Abū Dāʾūd 1669)
اسْتَأْذَنْتُ النَّبِيَّ ﷺ فَدَخَلْتُ بَيْنَهُ وَبَيْنَ قَمِيصِهِ قَالَ فَقُلْتُ يَا رَسُولَ اللهِ مَا الشَّيْءُ الَّذِي لَا يَحِلُّ مَنْعُهُ؟ قَالَ الْمَاءُ قُلْتُ يَا رَسُولَ اللهِ مَا الشَّيْءُ الَّذِي لَا يَحِلُّ مَنْعُهُ؟ قَالَ الْمَلحُ قَالَ قُلْتُ يَا رَسُولَ اللهِ مَا الشَّيْءُ الَّذِي لَا يَحِلُّ مَنْعُهُ؟ قَالَ أَنْ تَفْعَلَ الْخَيْرَ خَيْرٌ لَكَ