Hadith on Vows: The Prophet discouraged vows which are difficult and worship which is burdensome

Ibn Abbas reported: While the Prophet, peace be upon him, was giving a sermon, he saw a man standing and he asked about him. They said, “It is Abu Israel, who has vowed that he will stand and never sit down, he will never come into the shade nor will he speak to anyone, and he will be fasting.” The Prophet said, “Tell him to speak and let him come into the shade; make him sit down but let him complete his fast.”

[Sahih Bukhari, Book 78, Number 695]

عَنْ ابْنِ عَبَّاسٍ قَالَ بَيْنَا النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَخْطُبُ إِذَا هُوَ بِرَجُلٍ قَائِمٍ فَسَأَلَ عَنْهُ فَقَالُوا أَبُو إِسْرَائِيلَ نَذَرَ أَنْ يَقُومَ وَلَا يَقْعُدَ وَلَا يَسْتَظِلَّ وَلَا يَتَكَلَّمَ وَيَصُومَ فَقَالَ النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ مُرْهُ فَلْيَتَكَلَّمْ وَلْيَسْتَظِلَّ وَلْيَقْعُدْ وَلْيُتِمَّ صَوْمَهُ

صحيح البخاري كتاب الْأَيْمَانِ وَالنُّذُورِ مر وهو يطوف بالكعبة بإنسان يقود إنسانا بخزامة في أنفه فقطعها النبي صلى الله عليه وسلم بيده ثم أمره أن يقوده بيده