Hawzah News Agency – The commander of the faithful Imam Ali peace be upon him says:

إنَّ الأملَ يُذْهِبُ العقلَ، ويُكْذِبُ الوَعدَ، ويَحُثُّ علَى الغَفْلَةِ، ويُورِثُ الحَسْرَةَ. فأكْذِبوا الأملَ؛ فإنّه غَرُورٌ، وإنَّ صاحِبَهُ مَأزُورٌ.

'[False] Expectation drives reason away, breaks promises, encourages oblivion, and brings about grief. So distrust expectation, for it is deceitful and its addict is a sinner.'

Source: Bihar al-Anwar, v. 77, p. 293, no. 2