Sūrat ali-Imrān, verse 29
Surat Al-‘An`ām (The Cattle) - سورة الأنعام, verse 164.
The Messenger of Allah (ص) Nahj al-Fasahah p. 9
Reflect on what has passed of this world. Has any of it remained for anyone? Has anyone remained in it, be he noble or lowly, rich or poor, friend or enemy? Similarly, what has not yet happened of it resembles more closely that which has passed of it, than water resembles water. The Messenger of Allah said, ‘Death is enough of a warner; the intellect is enough of a guide; precaution is enough of a provision; worship is enough of an occupation; Allah is sufficient as an intimate friend; the Qur’an is enough of a clarification.’
And elsewhere, ‘Only affliction and trial remain of this world. If a person is saved, it is only by sincerely seeking refuge.' And Noah said, ’I found this world to be like a house with two doors. I entered through one of them and went out through the other.' Such is the state of the one who was saved by Allah: so what is the state of one who feels at ease in this world, relies on it, wastes his life by cultivating it, and is full of worldly demands?
Reflection is the mirror of good deeds and the expiation of bad deeds. It is the light of the heart, and guarantees ease to other people and success in obtaining betterment for the next abode; it allows one to foresee the outcome of one’s actions, and causes an increase in knowledge. Worship of Allah is unparalleled when accompanied by this quality. The Messenger of Allah said, ‘To reflect for an hour is better than worshipping for a year.’
The station of reflection is only obtained by him whom Allah has singled out for the light of gnosis (ma’rifah) and tawhid.