كتاب السنة
Read the English translation first, with the original Arabic directly underneath.
Abu Hurairah reported the Messenger of Allah (ﷺ) as saying:
If anyone summons other to follow right guidance, his reward will be equivalent to that of the people who follow him, without their rewards being diminished in any respect on that account; and if anyone summons others to follow error the sin of which sins being diminished in any respect on that account.
مَنْ دَعَا إِلَى هُدًى كَانَ لَهُ مِنَ الأَجْرِ مِثْلُ أُجُورِ مَنْ تَبِعَهُ لاَ يَنْقُصُ ذَلِكَ مِنْ أُجُورِهِمْ شَيْئًا وَمَنْ دَعَا إِلَى ضَلاَلَةٍ كَانَ عَلَيْهِ مِنَ الإِثْمِ مِثْلُ آثَامِ مَنْ تَبِعَهُ لاَ يَنْقُصُ ذَلِكَ مِنْ آثَامِهِمْ شَيْئًا