Imam al-Bayhaqi narrated through his chains to Imam al-Shafi’i (may Allah be pleased with him) that he said,
If people contemplate this Sura (i.e. Surat al-Asr), it would suffice them.
Imam Abu Dawud wrote that a person needs only the following four hadith for his religion:
Actions are judged only by intentions
من حسن أسلام المرء تركه ما لا يعنيه
Part of a person perfecting their Islam is to leave aside matters that do not concern them
لا يكون المؤمن مؤمنا حتى يرضى لأخيه ما يرضى لنفسه
No one’s faith is complete until he wishes for his brother what he wishes for himself
الحلال بين والحرام بين وبين ذلك أمور مشتبهات
What is permissible is clear and what is prohibited is clear, and what is other than that is uncertain.