Hadith on Customs: Follow the Prophet in religion, not worldly customs

Rafi’ ibn Khadij reported: The Prophet, peace and blessings be upon him, arrived in Medina and they were grafting trees. The Prophet said, “What are you doing?” They said, “We are grafting them.” The Prophet said, “Perhaps it would be better if you did not do it.” They abandoned the practice and the trees yielded less fruit. It was mentioned to the Prophet and he said, “Verily, I am only a human being. If I command you to do something in religion, adhere to it. If I command you to do something from my opinion, I am only a human being.

Source: Ṣaḥīḥ Muslim 2362

Grade: Sahih (authentic) according to Muslim

عن رَافِع بْن خَدِيجٍ قَالَ قَدِمَ نَبِيُّ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ الْمَدِينَةَ وَهُمْ يَأْبُرُونَ النَّخْلَ يَقُولُونَ يُلَقِّحُونَ النَّخْلَ فَقَالَ مَا تَصْنَعُونَ قَالُوا كُنَّا نَصْنَعُهُ قَالَ لَعَلَّكُمْ لَوْ لَمْ تَفْعَلُوا كَانَ خَيْرًا فَتَرَكُوهُ فَنَفَضَتْ أَوْ فَنَقَصَتْ قَالَ فَذَكَرُوا ذَلِكَ لَهُ فَقَالَ إِنَّمَا أَنَا بَشَرٌ إِذَا أَمَرْتُكُمْ بِشَيْءٍ مِنْ دِينِكُمْ فَخُذُوا بِهِ وَإِذَا أَمَرْتُكُمْ بِشَيْءٍ مِنْ رَأْيٍ فَإِنَّمَا أَنَا بَشَرٌ

2362 صحيح مسلم كتاب الفضائل باب وجوب امتثال ما قاله شرعا دون ما ذكره من معايش الدنيا على سبيل الرأي