Sayyiduna Ibn Umar (may Allah be pleased with them both) said: The Messenger of Allah (peace and blessings be upon him) said: "No person should make another person get up from his place so that he himself may sit there; rather, make room or create space in the gathering."
Hadith Referenceسنن دارمي / من كتاب الاستئذان / 2688
Hadith Gradingتحقیق (حسین سلیم أسد الدارانی):إسناده صحيح والحديث متفق عليه، [مكتبه الشامله نمبر: 2695]
Hadith Takhrijاس روایت کی سند صحیح اور حدیث متفق علیہ ہے۔ دیکھئے: [بخاري 6269، 6270] ، [مسلم 2177] ، [أبوداؤد 4828] ، [ترمذي 2749] ، [ابن حبان 586] ، [الحميدي 679]
Brief Explanation
(Commentary on Hadith 2687)
Among the etiquettes of gatherings is that whoever arrives first and sits at a place, he should not be made to stand up from his spot for the sake of any wealthy or prominent person, because doing so is an insult and humiliation to the one already seated.
Some scholars have said that this ruling is specific to certain gatherings, but the correct view is that this ruling is general.
It is reported about Sayyiduna Ibn Umar (radi Allahu anhuma) that if someone vacated his place for him, he would never sit there.