The Chapters on Expiation
11/3. Chapter:
One who takes an oath to follow a religion other than Islam
Sunan Ibn Majah
حَدَّثَنَا عَمْرُو بْنُ رَافِعٍ الْبَجَلِيُّ، حَدَّثَنَا الْفَضْلُ بْنُ مُوسَى، عَنِ الْحُسَيْنِ بْنِ وَاقِدٍ، عَنْ عَبْدِ اللَّهِ بْنِ بُرَيْدَةَ، عَنْ أَبِيهِ، قَالَ قَالَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ " مَنْ قَالَ إِنِّي بَرِيءٌ مِنَ الإِسْلاَمِ فَإِنْ كَانَ كَاذِبًا فَهُوَ كَمَا قَالَ وَإِنْ كَانَ صَادِقًا لَمْ يَعُدْ إِلَيْهِ الإِسْلاَمُ سَالِمًا " .
It was narrated from Abdullah bin Buraidah that his father told that : the Messenger of Allah (ﷺ) said: "Whoever says: 'I have nothing to do with Islam,' if he is lying then he is as he said, and if he is telling the truth, his Islam will not be sound."
Reference : Sunan Ibn Majah 2100In-book reference : Book 11, Hadith 11English translation : Vol. 3, Book 11, Hadith 2100