Hadithcore
Sahih Muslim, 43 c
sahih

A similar hadith has been reported on the authority of Anas (with another chain of transmitters) with the exception of these words:

that he again becomes a Jew or a Christian.

حَدَّثَنَا إِسْحَاقُ بْنُ مَنْصُورٍ، أَنْبَأَنَا النَّضْرُ بْنُ شُمَيْلٍ، أَنْبَأَنَا حَمَّادٌ، عَنْ ثَابِتٍ، عَنْ أَنَسٍ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم بِنَحْوِ حَدِيثِهِمْ غَيْرَ أَنَّهُ قَالَ ‏

‏ مِنْ أَنْ يَرْجِعَ يَهُودِيًّا أَوْ نَصْرَانِيًّا ‏

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References2 variants
In-Book Reference
Book 1, Hadith 74
USC-MSA web (English) reference
Book 1, Hadith 69 (deprecated numbering scheme)