[Abu Dawud, with a sound chain].
The narration in At-Tirmidhi is: The Messenger of Allah (ﷺ) was asked: "O Messenger of Allah! When two persons meet, who should greet the other first?'' The Messenger of Allah (ﷺ) said, "The person nearest to Allah (i.e., one who is more obedient and therefore closer to Allah will say: As-Salam first)."
ورواه الترمذي عن أبي أمامة رضي الله عنه: قيل: يا رسول الله، الرجلان يلتقيان، أيهما يبدأ بالسلام؟ قال: "أولاهما بالله تعالى" قال الترمذي : حديث حسن.
Reference | : Riyad as-Salihin 858 |
In-book reference | : Book 5, Hadith 15 |