His Manners and Ethics – The Prophet’s Tolerance (PBUH):
Prophet Muhammad’s tolerance was matchless, this is quite evident in the following examples:
* A Bedouin pulled the garment of the Prophet so violently that it caused marks on the shoulder of the Prophet (Peace Be upon Him), and the Bedouin said to the Prophet (PBUH): ‘Order for me from the fortune of Allah The Almighty which you have! You do not give me from your fortune, or the fortune of your father.’ The Prophet was tolerant with him, and he did not say to him anything except: ‘The fortune is the fortune of Allah, and I am his servant, and you will encounter the same of what you did to me, O Beduin.’ The Bedouin said: ‘No’ The Prophet said: ‘Why not?’ The Bedouin said: ‘You do not return the bad deed with another.’ The Prophet, Peace Be upon Him, laughed then he ordered for him a camel’s load of barley and a camel’s load of dates.
* It was never reported that Prophet Muhammad (Peace Be upon Him) offended any servant or woman, Mother of Believers Aisha, may Allah be pleased with her, said: "I have never seen Allah’s Messenger, Peace Be upon Him, avenge himself for a personal affliction, but if one transgressed a prohibited thing from those prohibited by Allah, then there was no one more angry than Allah’s Messenger. Whenever He (PBUH) was given a choice between two things, he always chose the one that was simple, if it did not lead to any type of sin". 
* Allah’s Messenger (Peace Be upon Him) was beyond tolerant. It was narrated that Zaid ibn Su’nah (the Jewish scholar) said about Prophet Muhammad (PBUH): “I recognized all of the signs of prophethood upon seeing the face of Muhammad save two signs that were not immediately evident: That his forbearance would precede his rashness, and that his forbearance would increase upon encountering excessive rashness.” Zaid ibn Su’nah reported the story as follows:
“One day, the Messenger of Allah (Peace Be upon Him) came out from his apartment with Ali ibn Abi Talib. A Bedouin, riding his camel, came to him and said:
“O Messenger of Allah! A group of my people of such and such a clan have accepted the faith and embraced Islam. I used to tell them that if they embraced Islam, there would be great abundance in their provision [due to divine blessing].
Now, however, they are facing famine due to lack of rain. I fear, O Messenger of Allah, that they will leave Islam out of greediness as they embraced it out of greediness. If you think it proper, send something that would suffice them.”
The Prophet looked to the man next to him, whom I believe was Ali, who replied:
“O Messenger of Allah! Nothing is left with us.'”
Zaid continues: “I approached the Prophet and said: “O Muhammad! If you desire, rent me such and such garden of dates for a fixed period of time.”
He replied: “No, but I’ll rent you a certain amount of date [palms] until such and such period without specifying the garden.”
I replied: “Alright.”
Thus, he rented them to me, and I opened my purse and took out eighty mithqaal of gold (350 grams) to pay for the particular dates for a fixed period. The Prophet handed the gold to the man and instructed him: “Help them through this and distribute it justly.”
Zaid ibn Su’nah goes on: “Two or three days before the fixed period was to end, the Messenger of Allah (Peace Be upon Him) came out with Abu Bakr, Umar, Uthman (May Allah be pleased with them), and a number of other Companions to offer the funeral prayer. When he finished the prayer and approached a wall to sit against it, I came to him, grabbed him by his shirt and cloak, and looked at him angrily and said: “O Muhammad! Why don’t you pay off my due?! By Allah, I know nothing of your family except deferment [on debts]. I know well of your people.”
Saying this I looked at Umar whose eyes were bulging and turning out of anger. He glared at me and said: “O enemy of Allah! Did you actually just say what I heard to the Messenger of Allah? Did you really just do to him what I saw? By the One Who holds my life in His hand, if I were not concerned with [the Prophet’s] leaving us, I would have struck your head with my sword.”
The Messenger of Allah, who was looking at me quietly and patiently, said: “O Umar! We don’t need this. I was more in need of your advice to pay off his loan well, and your advice to deal courteously. Go with him Umar, pay off his loan, and give him twenty extra saa` (44 kilograms) of dates because you frightened him.” Thus, Umar took me, paid off my debt, and gave me an extra twenty saa` of dates. I asked him: “Why this increase?” He replied: “The Messenger of Allah (peace and blessings be upon him) ordered me to give you this for me scaring you.”
I asked: “Do you recognize me, Umar?”
“No”, he said.
“I am Zaid ibn Su’nah”, I said.
“The scholar of the Jews?”
“Yes, the same one.”
“Then what made you behave and speak with the Messenger of Allah as you did?” he asked.
“O Umar!” I replied. “I recognized all of the signs of prophethood upon seeing the face of Muhammad save two signs that were not immediately evident: That his forbearance would precede his rashness, and that his forbearance would increase upon encountering excessive rashness. Now I have recognized these two signs as well.
Bear witness, O Umar! I am pleased with Allah as my Lord, with Islam as my religion, and with Muhammad as my Prophet. Also bear witness that I give half of my wealth – and I have plenty of wealth – in charity to the nation of Muhammad (Peace Be upon Him).”
Umar said: “Perhaps to some of them because your [money] won’t suffice for all of them.”
“Alright, to some of them.'”
Umar and Zaid returned to the Messenger of Allah (Peace Be upon Him) and Zaid publicly announced: “I bear witness that none is worthy of worship besides Allah, and I bear witness that Muhammad is His servant and Messenger and I believe in him.”
Thus, Zaid testified to the Prophet Muhammad’s message and took the pledge of allegiance on his hand. Zaid participated in a number of battles along with the Prophet and was martyred in the expedition of Tabuk whilst facing the enemy and not in retreat (May Allah be pleased with him). (The Narrator: Zaid ibn Su’nah, the Hadith Scholar: al-Madhi – The source: Tahdhib al-Kamal – A sound hadith)
* It was narrated that a man demanded his debts from Allah's Messenger (Peace Be upon Him) in such a rude manner that the companions of the Prophet intended to harm him, but the Prophet (PBUH) said, "Leave him, no doubt, for he (the creditor) has the right to demand it (harshly). Buy a camel and give it to him." They said, "The camel that is available is older than the camel he demands. "The Prophet (Peace Be upon Him) said, "Buy it and give it to him, for the best among you are those who repay their debts handsomely." (Narrated by al-Bukhari from Abu Hurirah)
His tolerance and patience are culminated in the slander incident (al-Ifk), it was an incident that caused him great grief and pain to him and his pure house. All the believers were shocked and in pain as well, because of the slander incident, which was an ordeal that the Prophet (Peace Be upon Him) had to endure, and based on that incident certain teachings and rulings become clear and definite for the Muslim nation. Many principals and values in his life represent the peak of the best conduct and manners, they are a milestone in the progress of humanity towards behavioral greatness, self-control and ethical perfection.
The slander incident is one of the social and psychological pressure and striving that Allah’s Messenger (PBUH) had to go through, and He (PBUH) successfully passed this hard time. The Almighty Lord sent him as a guide, bringer of good tidings, warner, a one who invites to Allah, by His permission, and an illuminating lamp. For his actions are guidance and his manners are light.
This biographical incident which happened during the lifetime of the Prophet (Peace Be upon Him), clarifies for the Muslim nation how to walk in the darkness if principals become obscure and the sun of truthfulness disappear behind the clouds of doubt and confusion.
Is there an uglier ordeal a man might encounter than when people badmouth and backbite the reputation of his house (i.e. his honor)?!
Even Allah’s Messenger did not escape this hardship, because his life is supposed to represent what people might go through in life, and his conduct is a role model for the Muslims, which they should follow and strive hard to emulate. In this incident, Prophet Muhammad (Peace Be upon Him) showed the conducted of a Prophet with heavenly manners, he was the best role model and teacher on how to pass this narrow dark tunnel in which young children become white-haired because of fear. 
When hypocrites failed in causing disappointment and confusion, and when they felt hopeless of defeating Muslims through their struggle with atheists and the Jews, and when they saw Prophet Muhammad (Peace Be upon Him) achieve great triumph in both fronts, they shifted towards another kind of war, i.e. a series of abuse and schemes against Muslims internally. They spread destructive rumors to shake the foundation of the Muslim society and cripple it. While Muslims were on their way back to Madinah after the Battle of Al-Mustaliq, Aisha, the Mother of Believers, went to answer the call of nature and when she came back to her camel, she found out that she lost a necklace she was wearing. So, she went back looking for it, until she found it. During this time, the army moved on and carried her houdaj, which is a small tent placed on the camel for women to ride inside, and put it on the camel, thinking she was riding inside because she was thin and very light. The carriers did not notice that she was not actually in the houdaj, the Muslims arrived to Madhinah leaving Aisha, may Allah be pleased with her, in the desert. She stayed in her place, knowing that they are going to miss her and return back to her when they found out she was not there. She felt sleepy and Safwan ibn al-Mu’atal – one of the good companions, may Allah be pleased with Him – lagged behind the army as he overslept. So, when he pass by Aisha, he said Inna lillahi wa inna ilaihi raji'un [we are for Allah and to Him we have to return], and he did not speak to her. He just dismounted from his camel, and made it kneel down for Aisha, may Allah be pleased with her to ride it. He moved on leading the camel by the nose string until, they reached the army where it had encamped for rest because of extreme heat. The hypocrites found it a good chance to spread rumors and lies, the most notorious among them was 'Abdullah b. Ubayy, the great hypocrite, he kept spreading rumors among people, till some of the believers fall into that trap, i.e. talking about this matter. The people who like to spread slander kept doing that, and the Prophet Muhammad (Peace Be upon Him) was very disturbed because of the claims of the hypocrites. He is still human, so he does not know the future or the unknown, and he does not know the aim of spreading such slander about his wife.
It was the wisdom of Allah Almighty that the revelation was delayed (in regard to this matter), for a month, till the hearts reached the throats, and the Prophet (PBUH) was afflicted. He did not know what to do before those rumors, if the revelation was an inner psychological feeling in the Prophet, PBUH, or something that is under his control or will, as some philosophers and their likes claim, he would have jumped to defend his honor with words and attributed them to the Lord, and claim that they are a revelation from heaven. But, Prophet Muhammad, Peace Be upon Him, never lied to people, let alone The Almighty Allah. In the Qur’an Allah says: “And if Muhammad had made up about Us some [false] sayings, We would have seized him by the right hand; Then We would have cut from him the aorta. And there is no one of you who could prevent [Us] from him.” (Al-Haqqa: 44-47) Allah’s Messenger (Peace Be upon Him) kept thinking about the matter, and consulted his close companions, who denied any claims about his wife and said they had not seen or heard anything bad about her. So, Allah’s Messenger addressed the people in the mosque and addressed this false accusation against Aisha, may Allah be pleased with her. He mounted the pulpit in the mosque and said: "To proceed: O people! Give me your advice regarding those people who have brought false charge about my family. By Allah, I find nothing in my wife but goodness and the person whom the people have mentioned in this connection is, according to my knowledge, a thoroughly pious person, and he did never get into my house but along with me."
These rumors and false accusation were spreading while Aisha did nothing about, because when she went back to Madinah, she got sick and she did not hear anything about what people were saying behind her back, no one told her. Yet, she felt that Allah’s Messenger, Peace Be upon Him, is not giving her the same attention he usually gives her especially when she was ill. Then, she came to know what people were saying about her, so she felt more ill. She asked Allah’s Messenger (PBUH) to visit her parents, and he permitted her. When she went to her father’s house, her mother confirmed the news to her, and she said: “Subhan Allah! Did the people really talk about that?” She kept crying that night, and could not sleep waiting that Allah would make the Prophet, Peace Be upon Him, see a vision, i.e. an honest dream, in which her innocence is clarified to him. There is no doubt that the Prophet, Peace Be upon Him, was in a great need for the revelation to feel assured and defend his honor. Allah’s Messenger, Peace Be upon Him, came to Aisha in her father’s house, and he glorified Allah and praised Him, then he said: “Now then O 'Aisha! , this is what has reached me about you and if you are innocent, Allah would Himself vindicate your honor, and if accidentally there has been a lapse on your part seek forgiveness of Allah; He will pardon you…” This was very hard on Aisha, may Allah be pleased with her, and she asked her parents to give Allah’s Messenger, PBUH, a reply, and both of them said that they do not know what to say to Allah’s Messenger, Peace Be upon Him. When Aisha was in despair that her case would be clarified, she quoted what Prophet Jacob said when he lost his son Joseph saying: “…so patience is most fitting. And Allah is the one sought for help against that which you describe.” (An-Nour: 11) Then she slept on her side, and gave them her back. At the same moment, the Prophet, Peace Be upon Him, said: "Have the good tidings O 'Aisha! Allah has revealed your innocence." The Almighty Allah defended the honor of Allah’s Messenger and revealed Quranic verses that are recited till the Day of Judgment, the Quran testifies that Aisha, the daughter of al-Siddiq Abu Bakr, is innocent and clarified her name from any slander or rumor, it shows the status and honorable position of Allah’s Messenger and His family for The Almighty. It was good that the slander incident happened whether on the long run or the short run, it was good because of its valuable consequences and lessons. Indeed, Almighty Allah speaks the truth when He says: “Do not think it bad for you; rather it is good for you…” (An-Nour: 11) 
Khalid Mohamed Khalid, Insaniyat Muhammad, Page 15 
Mohamed Abdel Rahman, Fi Rehab al-Sirah (In the Vastness of the Prophet’s Biography), Page 174, slightly abridged 
Sameh Qandeel, The Slander Incident (al-Ifk), available on: http://www.quranway.net/index.aspx?function=item&id=260&lang