This includes suppressing one's anger, and being gentle and humble. Allah Most High has said: "Surely, you are of tremendous nature," [Al-Qur'an 68:4] and, "Those who suppress their anger, and forgive other people – assuredly, Allah loves those who do good." [Al-Qur'an 3:134]
Bukhari and Muslim relate that 'Abdullah ibn 'Amr, radhiallahu 'anhu, said, "The Messenger of Allah, sallallahu 'alayhi wa sallam, was never immoderate or obscene. He used to say, 'Among those who are most beloved to me are those who have the finest character.'"
They also narrate that 'A'ishah, radhiallahu 'anha, said, "Never was the Messenger of Allah, sallallahu 'alayhi wa sallam, given the choice between two things without choosing the easier of them, as long as it entailed no sin. If it did entail sin, he was of all people the most remote from it. Never did he seek revenge for something done against himself; but when the sanctity of Allah was challenged, he would take vengeance for His sake alone."
The meaning of good character is the inclination of the soul towards gentle and praiseworthy acts. This may take place in one’s personal actions for Allah Most High, or in actions which involve other people.
In the former case, the slave of Allah has an open and welcoming heart for His commandments and prohibitions, and does what He has imposed on him happily and easily, and abstains from the things which He has forbidden him with full contentment, and without the least dissatisfaction.
He likes to perform optional good acts, and abstains from many permitted things for the sake of Allah Most High whenever he decides that to abstain in that way would be closer to perfect slavehood to Him. This he does with a contented heart, and without feeling any resentment or hardship. When he deals with other people, he is tolerant when claiming what is his right, and does not ask for anything which is not; but he discharges all the duties which he has towards others.
When he falls ill or returns from a trip, and no-one visits him, or when he gives a greeting which is not returned, or when he is a guest but is not honoured, or intercedes but is not responded to, or does a good turn for which he is not thanked, or joins a group of people who do not make room for him to sit, or speaks and is not listened to, or asks permission of a friend to enter, and is not granted it, or proposes to a woman, and is not allowed to marry her, or ask for more time to repay a debt, but is not given more time, or asks for it to be reduced, but is not permitted this, and all similar cases, he does not grow angry, or seek to punish people, or feel within himself that he has been snubbed, or ignored; neither does he try to retaliate with the same treatment when able to do so, but instead tells himself that he does not mind any of these things, and responds to each one of them with something which is better, and closer to goodness and piety, and is more praiseworthy and pleasing.
He remembers to carry out his duties to others just as he remembers their duties towards himself, so that when one of his Muslim brethren falls ill he visits him, if he is asked to intercede, he does so, if he is asked for a respite in repaying a debt he agrees, and if someone needs assistance he gives it, and if someone asks for favourable terms in a sale, he consents, all without looking to see how the other person had dealt with him in the past, and to find out how other people behave. Instead, he makes "what is better" the Imam of his soul, and obeys it completely.
Good character may be something which a man is born with, or it may be acquired. However, it may only be acquired from someone who has it more firmly rooted in his nature than his own. It is well known that a man of sensible opinion can become even more sensible by keeping the company of intelligent and sensible people, and that a learned or a righteous man can learn even more by sitting with other people orf learning or righteousness; therefore it cannot be denied that a man of beautiful character may acquire an even more beautiful character by being with people whose characters are superior to his own.
And Allah gives success!
From the book The Seventy-Seven Branches of Faith by Imam Al-Bayhaqi, published by The Quilliam Press, 1990, 1996.