Muwatta Malik, Book 15, Hadith 41 (USC-MSA)

Yahya related to me from Malik that he had heard that the Messenger of Allah, may Allah bless him and grant him peace, said, "No one calls to guidance without having the same reward as those who follow him without diminishing their rewards at all. And no one calls to error without having the same burdens as they do without diminishing their burdens at all."

وَحَدَّثَنِي عَنْ مَالِكٍ، أَنَّهُ بَلَغَهُ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏ "‏ مَا مِنْ دَاعٍ يَدْعُو إِلَى هُدًى إِلاَّ كَانَ لَهُ مِثْلُ أَجْرِ مَنِ اتَّبَعَهُ لاَ يَنْقُصُ ذَلِكَ مِنْ أُجُورِهِمْ شَيْئًا وَمَا مِنْ دَاعٍ يَدْعُو إِلَى ضَلاَلَةٍ إِلاَّ كَانَ عَلَيْهِ مِثْلُ أَوْزَارِهِمْ لاَ يَنْقُصُ ذَلِكَ مِنْ أَوْزَارِهِمْ شَيْئًا ‏" ‏ ‏.‏

sunnah.com

also referenced under: Book 15, Hadith 513 (In-Book)