Imaam Muhammad Bin Saaleh Al-Uthaymeen (rahimahullaah) stated:
If you see that your time is elapsing and your lifespan dwindling, whilst you have not produced anything beneficial nor useful, nor do you find a blessing in your time, then beware (lest you be from those included in) the statement of Allaah (The Most High):
وَلَا تُطِعْ مَنْ أَغْفَلْنَا قَلْبَهُ عَن ذِكْرِنَا وَاتَّبَعَ هَوَاهُ وَكَانَ أَمْرُهُ فُرُطًا
”And obey not him whose heart We have made heedless of Our Remembrance, one who follows his own lusts and whose affair has been lost.” [18:28]
That is: His affair has strayed and become disconcerted, and there is no blessing in it. It should be known that some people do remember Allaah, however he (or she) remembers (Allaah) with a heedless heart and for that reason he (or she) does not benefit. Indeed the person who remembers Allaah with his (or her) tongue and not with his (or her) heart is deprived of blessings in his (or her) deeds and time, until his (or her) affair is lost. You find him (or her) hanging around for long hours and he (or she) does not achieve anything. However, if his (or her) affair was with Allaah (i.e. truly spent in attentiveness to Allaah), he (or she) would have received blessings in all his (or her) actions. [Tafseer Soorah Al-Kahf of Imaam Muhammad Bin Saaleh Al-Uthaymeen (rahimahullaah)]  [End of quote]
So we remind ourselves of the following Aayaat, so that we do not lose hope in Allaah’s Mercy and rush to repentance. Allaah (The Most High) said:
قُلْ يَا عِبَادِيَ الَّذِينَ أَسْرَفُوا عَلَىٰ أَنفُسِهِمْ لَا تَقْنَطُوا مِن رَّحْمَةِ اللَّهِ ۚ إِنَّ اللَّهَ يَغْفِرُ الذُّنُوبَ جَمِيعًا ۚ إِنَّهُ هُوَ الْغَفُورُ الرَّحِيمُ
وَأَنِيبُوا إِلَىٰ رَبِّكُمْ وَأَسْلِمُوا لَهُ مِن قَبْلِ أَن يَأْتِيَكُمُ الْعَذَابُ ثُمَّ لَا تُنصَرُونَ
وَاتَّبِعُوا أَحْسَنَ مَا أُنزِلَ إِلَيْكُم مِّن رَّبِّكُم مِّن قَبْلِ أَن يَأْتِيَكُمُ الْعَذَابُ بَغْتَةً وَأَنتُمْ لَا تَشْعُرُونَ
Say: “O ‘Ibadi (My slaves) who have transgressed against themselves (by committing evil deeds and sins)! Despair not of the Mercy of Allah, verily Allah forgives all sins. Truly, He is Oft-Forgiving, Most Merciful.
“And turn in repentance and in obedience with true Faith (Islamic Monotheism) to your Lord and submit to Him, (in Islam), before the torment comes upon you, then you will not be helped.
“And follow the best of that which is sent down to you from your Lord (i.e. this Qur’an, do what it orders you to do and keep away from what it forbids), before the torment comes on you suddenly while you perceive not!” 
 This serious reminder was sent to us in Arabic via WhatsApp by Ustaadh Ismaa’eel Al-Maghribi [Arabic Teacher @ Redstone Academy (Birmingham) and Qur’aan teacher @ Masjid Salafi (Wright Street) -may Allaah preserve him and all his colleagues…Aameen)]
 Soorah Az-Zumar. Aayaat 53-55 [Note: We added these Aayaat as a reminder]