The best dhikr is lā ilāha illa Allah (there is no god but Allah), and the best supplication is Alhamdulillah (praise be to Allah)
عن جابر رضي الله عنه قال: سمعت رسول الله صلى الله عليه وسلم يقول: «أَفْضَلُ الذِّكْرِ: لَا إِلَهَ إِلَّا اللهُ، وَأَفْضَلُ الدُّعَاءِ: الْحَمْدُ لِلهِ».
Jābir (may Allah be pleased with him) reported: I heard the Messenger of Allah (may Allah’s peace and blessings be upon him) say: "The best dhikr is lā ilāha illa Allah (there is no god but Allah), and the best supplication is Alhamdulillah (praise be to Allah)."
Narrated by At-Tirmidhi and An-Nasā’i in Al-Kubra and by Ibn MājahGradeHasan
Explanation
The Prophet (may Allah's peace and blessings be upon him) informs us that the best dhikr (remembrance of Allah) is Lā ilāha illa Allah (there is no god but Allah), which means that no one is worthy of worship except Allah; and that the best supplication is Alhamdulillah (praise be to Allah), and it means acknowledgment that Allah Almighty is the Bestower of favors and the One worthy of possessing the attributes of perfection and excellence.
Benefits
This urges us to mention Allah often by uttering the testimony of faith and the supplication of praise.
Reference
سنن الترمذي (5/ 393) (3383).
نزهة المتقين شرح رياض الصالحين، لمصطفى الخِن وغيره (2/ 984).
زاد المعاد في هدي خير العباد، ابن قيم الجوزية (1/ 36).
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