How does the the wahi (inspiration) come to you? He said: At times it comes to me like the ringing of a bell and that is most severe for me and when it is over I retain that (what I had received in the form of wahi), and at times an Angel in the form of a human being comes to me (and speaks) and I retain whatever he speaks. (Using translation from Muslim 2333b)
أَنَّ الْحَارِثَ بْنَ هِشَامٍ سَأَلَ رَسُولَ اللهِ ﷺ كَيْفَ يَأْتِيكَ الْوَحْيُ؟ قَالَ أَحْيَانًا يَأْتِينِي فِي مِثْلِ صَلْصَلَةِ الْجَرَسِ وَهُوَ أَشَدُّهُ عَلَيَّ ثُمَّ يُفْصَمُ عَنِّي وَقَدْ وَعَيْتُ وَأَحْيَانًا يَأْتِينِي مَلَكٌ فِي مِثْلِ صُورَةِ الرَّجُلِ فَأَعِي مَا يَقُولُ