Mishkat al-Masabih
Ibn ‘Abbas said that "Water is necessary only when there is an emission” applies to a dream. Tirmidhi transmitted it, but I have not found it in the two Sahihs.
وَقَالَ ابْنُ عَبَّاسٍ: إِنَّمَا الْمَاءُ مِنَ الْمَاءِ فِي الِاحْتِلَامِ. رَوَاهُ التِّرْمِذِيُّ وَلَمْ أَجِدْهُ فِي الصَّحِيحَيْنِ
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