Musnad Ahmad Hadith 22052

It is narrated from Mu'adh (may Allah be pleased with him) that when the Holy Prophet (ﷺ) sent him to Yemen, he himself went out to see him off and kept advising him along the way. Mu'adh (may Allah be pleased with him) was riding while the Holy Prophet (ﷺ) was walking alongside him. When the Holy Prophet (ﷺ) finished giving him advice, he said, "Mu'adh! It may be that you will not meet me next year, or it may be that next year you will pass by my mosque and my grave." Mu'adh (may Allah be pleased with him) began to weep out of grief at the separation from the Holy Prophet (ﷺ). Then the Holy Prophet (ﷺ) turned his face towards Madinah Munawwarah and said, "The people closest to me among all are the God-fearing, whoever they may be and wherever they may be."