Sayyiduna Abu Hurairah (may Allah be pleased with him) narrates: The Noble Prophet (peace and blessings be upon him) said:“Whoever does not mention the name of Allah at the beginning, it is as if he did not perform ablution at all, and whoever did not perform ablution, it is as if he did not pray at all, and whoever does not love me, it is as if he did not believe in me at all, and whoever does not love the Ansar, it is as if he does not love me either.”

Rabee’ bin Abdur Rahman narrates from his father, from his grandfather (from Sayyiduna Abu Sa’eed al-Khudri, may Allah be pleased with him) that the Prophet Muhammad (peace and blessings be upon him) said:“The ablution of the one who does not mention the name of Allah at its beginning (i.e., does not say Bismillah) is not valid.”

Lady Aisha (may Allah be pleased with her) narrates: When the Prophet Muhammad (peace and blessings be upon him) was about to touch the (vessel for) ablution, he would first recite Bismillah. The narrator named Abu Badr has stated this (that is, in the narration these words are present): "When the Prophet Muhammad (peace and blessings be upon him) would get up for ablution, he would recite Bismillah, then pour water from the vessel onto his hand."

Rabah bin Abdur Rahman narrates from his grandmother, who reports from her father: The Prophet Muhammad (peace be upon him) said: "The prayer of the one who does not have ablution is not valid, and the ablution of the one who does not mention the name of Allah at the beginning (i.e., does not recite Bismillah) is not valid. And the one who does not have faith in Allah does not have faith in me, and the one who does not love the Ansar does not have faith in me."

This narration is also transmitted with another chain of transmission.

Rabah bin Abdur Rahman narrates from his grandmother, who narrates from her father: The Prophet Muhammad (peace be upon him) said: "There is no prayer without ablution, and the ablution of the one who does not mention the name of Allah at the beginning is not valid. And the one who does not believe in me does not believe in Allah Almighty, and the one who does not love the Ansar, in reality, does not believe in me."

Rabah bin Abdur Rahman narrates from his grandmother: She heard her father, Sayyiduna Saeed bin Zaid bin Amr (may Allah be pleased with him), saying that he heard the Prophet Muhammad (peace and blessings be upon him) say: "The prayer of a person who does not have ablution is not accepted, and the ablution of a person who does not recite 'Bismillah' at the beginning is not accepted."

Rabah bin Abdur Rahman narrates from his grandmother: She heard her father, Sayyiduna Saeed bin Zaid bin Amr bin Nufail (may Allah be pleased with him), saying: I heard the Prophet Muhammad (peace and blessings be upon him) say: "The prayer of a person who does not have ablution is not accepted, and the ablution of the one who does not recite 'Bismillah' at the beginning is not accepted."

This narration is also transmitted with another chain of transmission.

Sayyiduna Abdullah (bin Mas’ud, may Allah be pleased with him) narrates: I heard the Noble Prophet (peace and blessings of Allah be upon him) say:“When a person begins to perform wudu, he should first recite ‘Bismillah’, because this will purify his entire body. If he does not recite ‘Bismillah’ before wudu, then only that part will be purified upon which water is applied. And when a person completes his wudu, he should recite the testimony of faith: There is no deity except Allah, and Muhammad (peace and blessings of Allah be upon him) is Allah’s special servant and Messenger. When he recites this, the gates of the heavens will be opened for him.”The narrator of this narration, Yahya bin Hashim, is weak.