In The Name of Allaah, The Most Merciful, The Bestower of Mercy.
Allaah [The Exalted] said:
إِنَّ ٱلۡإِنسَـٰنَ لَفِى خُسۡرٍ
إِلَّا ٱلَّذِينَ ءَامَنُواْ وَعَمِلُواْ ٱلصَّـٰلِحَـٰتِ وَتَوَاصَوۡاْ بِٱلۡحَقِّ وَتَوَاصَوۡاْ بِٱلصَّبۡرِ
By Al-‘Asr (the time). Verily! The human is in loss; except those who believe (in Islamic Monotheism) and do righteous good deeds, enjoin one another to the truth and enjoin one another to patience. [Surah Al-Asr]
Indeed, Allaah placed humans in two categories – the loser and the gainer. The gainer is the one who sincerely exhorts himself with Eemaan and righteous deeds; sincerely exhorts the people by enjoining truth, which incudes teaching the truth and guiding to it; and enjoining patience, which also includes that he himself exercises patience. The Surah comprises of the two sincere exhortations, two characteristics of human perfection and the highest level of two types of strengths, expressed in the shortest, the most concise and clearest wording, the best preamble and the best precision in the suitable place (or subject matter).
As for the two sincere exhortations, they are the person’s sincere exhortation of himself and his brother in Islam by enjoining truth and exercising patience upon the path. As for the two characteristics of human perfection, they are the person’s self-perfection and enabling others to attain self-perfection (i.e. by help of Allaah). As for perfection of the two strengths, the soul has two strengths and they are: the strength of knowledge and sound observation, and these two affairs are perfected through Eemaan; the strength of sound intent, love (for everything praiseworthy, especially love for Allaah) and knowledge, and these affairs are perfected through righteous deeds (i.e. deeds carried out sincerely for the sake of Allaah and in conformity with the authentic Sunnah), and this cannot be accomplished except through patience.
Therefore, there are three affairs carried out by the person and then he enjoins them on others- perfection of the strength of knowledge through Eemaan, perfection of the strength of action through righteous deeds, being consistent upon that with patience and commanding others with it. And by way of these three affairs, he becomes a participant and one attributed to them, teaching and calling to them. This is the absolute gain, and in estimation of whatever he misses of this gain, he incurs some loss the like thereof. And Allaah’s Aid is sought and to Him we entrust all affairs! [ Al-Kalaam Alaa Mas’alah As-Samaa 404. slightly paraphrased]
Repentance – By Imaam Ibnul Qayyim and Imaam Abdul Azeez Bin Baaz [may Allaah have mercy upon them]