It is narrated from Basheer bin Yasaar (may Allah have mercy on him), he says that no one could precede Sayyiduna Ibn Umar (may Allah be pleased with them both) in greeting (salaam).
Hadith Referenceالادب المفرد / كتاب السلام / 982
Hadith Gradingالألبانی:صحيح
Hadith Takhrij«صحيح : تفرد به المصنف»
Explanation & Benefits
Shaykh Maulana Usman Muneeb
Benefits and Issues: The point is that Sayyiduna Ibn Umar (radi Allahu anhuma) would always initiate the greeting of salam, and no one could surpass him in this virtuous act. The instruction that “the younger should greet the elder, and the rider should greet the one walking” is for recommendation (istihbab). In any case, the one who initiates is superior.
Source: Fadlullah al-Ahad: Urdu Commentary on al-Adab al-Mufrad, Page: 982