Surah Al-Ahzab, Verse 48: وَلَا تُطِعِ الْكَافِرِينَ وَالْمُنَافِقِينَ وَدَعْ أَذَاهُمْ وَتَوَكَّلْ عَلَى اللَّهِ وَكَفَىٰ بِاللَّهِ وَكِيلًا And be not compliant to the unbelievers and the hypocrites, and leave unregarded their annoying talk, and rely on Allah; and Allah is sufficient as a Protector.
Surah Al-Ahzab, Verse 45: يَا أَيُّهَا النَّبِيُّ إِنَّا أَرْسَلْنَاكَ شَاهِدًا وَمُبَشِّرًا وَنَذِيرًا O Prophet! surely We have sent you as a witness, and as a bearer of good news and as a warner
"The Jews split into 71 sects, and the Christians split into 72 sects. My nation is going to split into 73 sects, and all of them will be in the Hellfire except one."
It was said, “Who are they (that one Saved Sect), O Messenger of Allaah?” He replied,
"They those who are upon what I and my Companions are upon."”
– Prophet Muhammad (pbuh)