He has found the taste of faith (iman) who is content with Allah as his Lord, with Islam as his religion (code of life) and with Muhammad ﷺ as his Prophet.
أَنَّهُ سَمِعَ رَسُولَ اللَّهِ ﷺ يَقُولُ ذَاقَ طَعْمَ الإِيمَانِ مَنْ رَضِيَ بِاللَّهِ رَبًّا وَبِالإِسْلاَمِ دِينًا وَبِمُحَمَّدٍ رَسُولاً