Hadith 225

Narrated Ibn 'Umar (RA): I asked Bilal (RA), "How did you observe the Prophet (SAW) replying to their (the Companions) salutation while he was engaged in prayer?" He (Bilal) said, "He used to do this way," and he (Bilal) demonstrated by spreading his palm. [Reported by Abu Dawud and at-Tirmidhi. The latter graded it Sahih (authentic)].