“Be conscious (Taqwa) of Allah wherever you are. And follow up a bad deed with a good deed and it will wipe it out. And behave towards the people with a good behaviour.” [Tirmidhi]
Ibn Rajab states in his commentary of this hadith: “Having good character is a characteristic of taqwa. Taqwa cannot be complete without it. It was mentioned here by itself due to the need for explicitly explaining that point. Many people think that taqwa implies fulfilling the “rights of Allah” without fulfilling the rights of humans. Therefore, the Prophet (peace be upon him) explicitly stated that he must deal with people in a kind manner. Many of those who take advantage of fulfilling the rights of Allah, and are attached to love for Him, fear of Him and obedience to Him, neglect the rights on the humans, either completely or partially. There are very few people who combine together the fulfilling of the rights of Allah and of His servants. The only ones who have the strength to do that are those who are complete in their taqwa from among the prophets and the sincere ones.” [Jaami, vol 1, p. 454] In this hadith, the Prophet advised the person to have a certain behaviour. This demonstrates that a person can change and determine his behaviour. He can do those acts that are of good behaviour and character to the point that he grows accustomed to them. He can grow so accustomed to them that they do become his nature and character. Hence, a person can change his character, and, if he is of bad character, then, following this advice of the Prophet, he must work to change his character.
When talking about the purpose for which he had been sent, the Messenger of Allah stated, “I have been sent for the purpose of perfecting good morals.” [Al-Hakim] That is, he was to show the manners and behaviour consistent with the belief in Allah.
In another hadith, the Messenger of Allah said, “I am a guarantor of a house in the highest part of Paradise for the one who makes his behaviour good.” [Abu Dawud] In yet another hadith, the Prophet described piety itself as being good character. Hence, it is an essential part of being pious. The Prophet said, “Piety and righteousness is being of good character.” [Muslim] How pleasing good character is to Allah can be seen by the weight that Allah will give it on the scales on the Day of Judgment. The Messenger of Allah said, “There is nothing heavier in the scales than good character.” [Ahmad, Abu Dawud]. In another hadith that gives a similar impression, the Prophet said, “A believer reaches, due to his good character, the level of the one who fasts and performs the night prayer.” [Abu Dawud] The way to improve one’s character is to look at the example of the Prophet (peace be upon him). One should try to emulate his behaviour in as many different circumstances as possible. If a person does that, then he will be moving toward the noblest character.
Compiled From:”Commentary on the Forty Hadith of al-Nawawi” – Jamaal al-Din M. Zarabozo, pp. 720-723