It is narrated from a Companion of the Ansar (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) passed by him while he was (supplicating) with both his palms spread out, and he (peace and blessings be upon him) said (instructing him to point with the index finger as a sign of Allah's oneness): "Ahhid fa-innahu ahad (Point with one (finger), for He (Allah) is One and Unique)."
Imam al-Nasa'i recorded this hadith in his Sunan, and its meaning is that during supplication it is recommended to point with the index finger as an affirmation of the oneness of Allah Almighty.
Hadith Referenceالمطالب العالية بزوائد المسانيد الثمانية / كتاب الأذكار والدعوات / 3355
Hadith Gradingمحدثین:إسناده صحيح، منقطع
Hadith Takhrij«حکم الحدیث المطالب العالیہ محققاً تنسیق د. سعد بن ناصر بن عبد العزيز الشَّثري- مکتبہ شاملہ :هذا الحديث بهذا الإسناد رجاله ثقات، لكنه منقطع » «أخرجه المطالب العالية لابن حجر برقم: 3356، وأخرجه مصنف ابن أبي شيبة برقم: 30312»
A Companion of the Ansar narrates from his grandfather (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) passed by him while he was (supplicating and) pointing with (the fingers of) both his hands, and he (peace and blessings be upon him) said (instructing him to use one finger in keeping with tawhid): "Ahhid fa-innahu ahad (Point with one (finger), for He (Allah Almighty) is One)."
Imam Abu Bakr bin Abi Shaybah recorded this narration, and its supporting narrations are found in Sunan al-Nasa'i (1273) and Musnad Ahmad (15914); according to the hadith scholars its chain is of hasan (good) grade.
Hadith Referenceالمطالب العالية بزوائد المسانيد الثمانية / كتاب الأذكار والدعوات / 3356
Hadith Gradingمحدثین:إسناده ضعيف
Hadith Takhrij«حکم الحدیث المطالب العالیہ محققاً تنسیق د. سعد بن ناصر بن عبد العزيز الشَّثري- مکتبہ شاملہ :هذا الحديث بهذا الإسناد ضعيف » «أخرجه المطالب العالية لابن حجر برقم: 3355، وأخرجه مصنف ابن أبي شيبة برقم: 30312»