It is narrated from Sayyiduna Jabir (may Allah be pleased with him) that he heard the Prophet (peace and blessings be upon him) say: After the period of cessation of revelation had passed, one day I was walking when I heard a voice from the sky. I looked up and saw the same angel who had come to me in the Cave of Hira, sitting on a throne between the sky and the earth. Seeing this, I was overcome with trembling and I went to Khadijah and said, "Cover me with a thick blanket." So she covered me with a blanket. On this occasion, Allah revealed this verse: "O you who covers himself [with a cloak]." After that, the series of revelations began in succession.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 15033
Hadith Gradingحکم دارالسلام:حديث صحيح، وهذا إسناد حسن من أجل محمد بن أبى حفصة، وهو متابع، وانظر: 14287