The Prophet ﷺ said, "Among the best of your names are Abdullah and Abdul-Rahman."
حدثنا وكيع حدثنا العمري عن نافع
عن النبي ﷺ قال إن من أحسن أسمائكم عبد الله وعبد الرحمن
Its isnad is sahih. Muslim related it, 2:167, through Abbad bin Abbad, from Ubaydullah bin Umar and his brother Abdullah, who is the Umari, the teacher of Waki here, with the wording, "The names most beloved to Allah among your names are..." Abu Dawud likewise related it, 4:443, through Abbad, from Ubaydullah alone. Tirmidhi related it, 4:28-29, through Abdullah bin Uthman bin Khuthaym, from Nafi. Tirmidhi said, a hasan gharib hadith from this route, and his commentator also attributed it to Ibn Majah. Munziri fell short in Tahdhib Abu Dawud when he attributed it to Sahih Muslim alone. See also 1381, 1382.