A hadith was reported in Abu Dawud: (There is no gharar in prayer, and no returning of the salam). Some people used this to refute returning the salam by gesture during prayer. Al-Tahawi mentioned that the Prophet

The questioner : ... The first part contains a hadith in Sunan Abu Dawud that the Prophet (peace and blessings be upon him): Some people used this as evidence to prohibit offering the salam to a person who is praying. This is the first part. As for the second part, Al-Tahawi mentioned in his Sharh Ma'ani al-Athar some points of doubt regarding the rejection of this Sunnah, which is the Sunnah of returning the salam by gesture during prayer. Among the things he mentioned is that it is established that the Prophet (peace and blessings be upon him) returned the salam to Ibn Mas'ud after the prayer with his tongue. He said, if the gesture of the hand were sufficient and considered a return of the salam spoken when it was offered to the person praying, the Prophet (peace and blessings be upon him) would not have returned the salam to Ibn Mas'ud after the prayer. So, he turned the issue around, O Shaykh.

The Shaykh : I do not recall that the Prophet (peace and blessings be upon him), in the hadiths that have passed before me regarding the story of Ibn Mas'ud, combined returning the salam by gesture while he was praying with returning the salam verbally after exiting the prayer. I do not recall this. And naturally, we do not claim to have complete knowledge and encompassing understanding, especially since the era is far from this topic. However, we say: if it is authentic that the Prophet (peace and blessings be upon him) returned the salam verbally, then what you related from Al-Tahawi is not applicable. That is because returning the salam by gesture from the Messenger of Allah (peace and blessings be upon him and his family) to Ibn Mas'ud when he greeted him verbally does not mean that it is not permissible to express the verbal salam as a return after finishing the prayer. First, then, it does not negate the legitimacy of the one coming offering the salam verbally to the person praying, and the legitimacy of the person praying returning the salam by gesture. There is absolutely no contradiction between this and that. This is what comes to my mind to refute this doubt. But I am wondering in my mind right now, are you newly acquainted with what you mentioned from Al-Tahawi?

The questioner : Yes, my Shaykh.

The Shaykh : And he said that in a narration there, the Messenger combined returning the salam verbally in the prayer, excuse me, between returning the salam by gesture in the prayer and verbally after the prayer?

The questioner : No, I do not think there is a narration with that. No, I meant, he returned the salam to Ibn Mas'ud after the prayer.

The Shaykh : That is what I understood from you.

The questioner : And in some narrations, from the hadith of Ibn Mas'ud himself, that he said: The hadith is separate, meaning from the other, meaning the two hadiths are separate from Ibn Mas'ud.

The Shaykh : Okay, one of them.

The questioner : One of them came that "the Prophet (peace and blessings be upon him) returned the salam to me after the prayer," and the other came that "the Prophet (peace and blessings be upon him) returned the salam to him by gesture while he was praying."

The Shaykh : Okay, and in both hadiths, Ibn Mas'ud offered the salam to the Prophet (peace and blessings be upon him) while he was praying?

The questioner: Yes.

The Shaykh : And in both hadiths.

The questioner : Yes, and we will review it, if Allah wills, and inform you of that.