In the year that Umar bin Abdul Aziz (Rahimahullah - May Allah have mercy upon him) assumed the caliphate, he sent a message to his son, Abdul Malik, who at that time was in al-Madinah. It was referring Abdul Malik and his brothers.
'Whoever desires Jannah (Paradise) and wants to escape the Nar (Fire) now is when repentance is accepted and sins are forgiven before the appointed tme is decreed, upon which nothing else can be offered to Allah, no ransom will be accepted for the deeds you bear and no trick can help conceal what you secretly hid inside. Everyone will have their deeds returned to them and they will be split up into ranks. Therefore whoever obeys Allah, (let him) repent for that Day, and woe unto him who disobeys Allah, the Majestic.'
In another narration of the same account, he urges his son to remember and thank Allah, the Sublime, and to watch his speech and actions.
'Remember the favour Allah bestowed upon you and your father and if you are able to engage your tongue with remembrance, glorification and praise of Him as much as you possibly can then do so; for the best speech that you can put forth is praise and thanks to Allah and best thing to put a stop to bad speech is giving praise and thanks to Allah.'
Reference: Sirat Umar bin Abdul Aziz (The Biography of Umar bin Abdul Aziz) by Ibn al-Jawzi, p. 298, pp. 1156; Abu Hafs al-Mala (1266).
Excerpts from The Rightly-Guided Caliph & Great Reviver Umar bin Abdul Aziz by Dr. Ali Muhammad As Sallabi
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