Ibn Kathir mentions in his famous book Al Bidaayah wal-Nihaayah:
فأظهر الله كذبه ولصق به لقب الكذاب، وأراد إظهار كرامات تشبه معجزات النبي ، فقد ذكر ابن كثير في البداية أنه بصق في بئر فغاض ماؤها، وفي أخرى فصار ماؤها أجاجاً، وسقى بوضوئه نخلا فيبست، وأتى بولدان يبرك عليهم فمسح على رؤسهم فمنهم من قرع رأسه ومنهم من لثغ لسانه، ودعا لرجل أصابه وجع في عينيه فمسحهما فعمي.
Allah exposed his lies and from then on the title of 'The Liar' has always been associated with his name. He wished to show miracles (to the people) similar to the Miracles of the Prophet (peace be upon him)
Ibn Katheer has mentioned in His Book Al-Bidaayah that he (Musailimah) Spat in a well, and its water dwindled and dried up. And he spat in another well and that water turned to bitter salty water.
He watered a date tree with the excess water from his Wudhoo' and the tree dried up and died.
Two boys were brought to him so that he may bless them and so he wiped their heads with his hand, as a result of that, the head of one of them became bald and the other developed a speech defect.
A man who was suffering from an ailment in his eyes came to him (for a cure) but when he wiped them, the man became blind.
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