Ayesha reported,

The first form of revelation that came to the Messenger of Allah ﷺ was true dreams in his sleep. He never saw a dream but that it came to pass as clearly as the break of dawn. Then solitude was made dear to him, and he would withdraw to the cave of Hira, where he would devote himself to worship for a number of nights before returning to his family. He would take provisions for that period, then come back to Khadijah and take provisions for a like stay, until the truth came to him while he was in the cave of Hira.The angel came to him and said, "Recite."He replied, "I am not one who recites."The Prophet ﷺ said, "He took hold of me and pressed me until I could bear no more, then released me and said, 'Recite.' I said, 'I am not one who recites.' So he took hold of me and pressed me a second time until I could bear no more, then released me and said, 'Recite.' I said, 'I am not one who recites.' So he took hold of me and pressed me a third time, then released me and said, 'Recite in the name of your Lord who created. He created man from a clinging clot. Recite, and your Lord is the Most Generous, who taught by the pen, taught man what he did not know' [Alaq 96:1–5]."The Messenger of Allah ﷺ returned with these words, his heart trembling, and went in to Khadijah bint Khuwaylid and said, "Wrap me up, wrap me up."They wrapped him until the terror left him. Then he told Khadijah what had happened and said, "I feared for myself."Khadijah said, "Never. By Allah, Allah will never disgrace you. You keep the ties of kinship, you carry the burdens of the weak, you provide for the destitute, you host the guest, and you help others in times of genuine hardship."Then Khadijah took him to Waraqah bin Nawfal bin Asad bin Abdul-Uzza, her cousin, a man who had become a Christian in the days before Islam. He used to write in Hebrew script, and he would write out from the Gospel in Hebrew as much as Allah willed him to write. He was by then a very old man who had gone blind.Khadijah said to him, "Cousin, listen to what your nephew has to say."Waraqah said, "Nephew, what have you seen?"The Messenger of Allah ﷺ told him what he had seen.Waraqah said, "This is the same keeper of divine secrets whom Allah sent down to Musa. I wish I were a young man during your mission. I wish I could still be alive when your people drive you out."The Messenger of Allah ﷺ asked, "Will they really drive me out?"Waraqah replied, "Yes. No man has ever brought what you have brought without being met with hostility. If I live to see your day, I will support you with all my strength."But Waraqah died not long afterward, and the revelation paused for a time.

عن عائشة قالت

أول ما بدئ به رسول الله ﷺ من الوحي الرؤيا الصالحة في النوم، فكان لا يرى رؤيا إلا جاءت مثل فلق الصبح ثم حبب إليه الخلاء وكان يخلو بغار حراء فيتحنث فيه- وهو التعبد. الليالي ذوات العدد قبل أن ينزع إلى أهله، ويتزود لذلك، ثم يرجع إلى خديجة فيتزود لمثلها، حتى جاءه الحق وهو في غار حراء فجاءه الملك فقال: اقرأ قال: ما أنا بقارئ قال: فأخذني فغطني حتى بلغ مني الجهد ثم أرسلني، فقال: اقرأ قلت: ما أنا بقارئ فأخذني فغطني الثانية حتى بلغ مني الجهد ثم أرسلني فقال: اقرأ فقلت: ما أنا بقارئ فأخذني فغطني الثالثة ثم أرسلني فقال: {اقرأ باسم ربك الذي خلق خلق الإنسان من علق اقرأ وربك الأكرم الذي علم بالقلم علم الإنسان ما لم يعلم} [سورة العلق: ١- ٥]. فرجع بها رسول الله ﷺ يرجف فؤاده، فدخل على خديجة بنت خويلد رضي الله عنها فقال: زملوني زملوني، فزملوه حتى ذهب عنه الروع، فقال لخديجة وأخبرها الخبر: لقد خشيت علي نفسي فقالت خديجة: كلا والله ما يخزيك الله أبدا، إنك لتصل الرحم، وتحمل الكل وتكسب المعدوم، وتقري الضيف، وتعين على نوائب الحق. فانطلقت به خديجة حتى أتت به ورقة بن نوفل بن أسد بن عبد العزى ابن عم خديجة، وكان امرءا تنصر في الجاهلية وكان يكتب الكتاب العبراني فيكتب من الإنجيل بالعبرانية ما شاء الله أن يكتب وكان شيخا كبيرا قد عمي فقالت له خديجة يا ابن عم اسمع من ابن أخيك فقال له: ورقة يا ابن أخي ماذا ترى، فأخبره رسول الله ﷺ خبر ما رأى فقال له: ورقة هذا الناموس الذي نزل الله على موسى، يا ليتني فيها جذع ليتني أكون حيا إذ يخرجك قومك، فقال رسول الله ﷺ: أو مخرجي هم؟ قال: نعم، لم يأت رجل قط بمثل ما جئت به إلا عودي، وإن يدركني يومك أنصرك نصرا مؤزرا. ثم لم ينشب ورقة أن توفي وفتر الوحي.