Mercy in Islam

All chapters in the Quran, except one (Reptentance Chapter), begin with the following words:

Bismillahi ar-Rahman ar-Rahim or in the name of Allah, Most Gracious, Most Merciful

Allah SWT could have used other attributes in its place, but he chose these two which show their significance. God's Mercy precedes his other attributes. Each worshipper repeats the attribute of mercy 68 times/day during his 5 daily prayers.

Allah SWT says in the Quran:

Say: 'O My servants who have transgressed against your own souls:
do not despair of God's mercy, for God forgives all sins. It is He who is the Forgiving, the Merciful.' (39:53)

And when those who believe in Our revelations come unto thee, say: Peace be unto you! Your Lord hath prescribed for Himself mercy, that whoso of you doeth evil through ignorance and repenteth afterward thereof and doeth right, (for him) lo! He is Forgiving, Merciful. [Al An'aam: (6)054]

The prophet of Islam said in a hadith narrated by Abu Huraira: "When Allah created the Creation, He wrote in His Book--and He wrote (that) about Himself, and it is placed with Him on the Throne--'Verily My Mercy overcomes My Anger"

This is a clear indication that God's mercy precedes his anger and that kindness precedes harshness.

Allah SWT says:

We sent thee not, but as a Mercy for all creatures. [The Prophets: 107]

The Prophet says: "Allah will not give mercy to anyone, except those who give mercy to others"
The scholars agree that in "others" the Prophet was referring to all of God's creation. No exceptions can be made based on religion, colour, creed, etc.
Ibn Batta said: "This hadith encourages people to show mercy toward all the creation, including believers, disbeliever and beasts, be them owned or not. Animals should be supplied with food to eat and water to drink and should not be overloaded or beaten."

In the same hadith, the Prophet's companions said: Oh, Allah's Apostle, all of us give mercy. The prophet replied: "Not through each of you giving mercy to his company, but through giving mercy to all people."

The Prophet once narrated a story about a woman who was cruel to her cat, and was sent to hell for her wrongdoing. It is clear that God rewards kindness to animals and punishes those who are cruel.

Allah's Apostle said: "While a man was walking he felt thirsty and went down a well and drank water from it. On coming out of it, he saw a dog panting and eating mud because of excessive thirst. The man said, 'This (dog) is suffering from the same problem as that of mine. So he (went down the well), filled his shoe with water, caught hold of it with his teeth and climbed up and watered the dog. Allah thanked him for his (good) deed and forgave him." The people asked, "O Allah's Apostle! Is there a reward for us in serving (the) animals?" He replied, "Yes, there is a reward for serving any animate"

The Prophet also told his companions that Paradise was open for a prostitute who was merciful toward a dog. The Prophet said: "A dog was going around the brink of a well in an extremity of thirst, when a loose woman of the Bani Israel espied it. She lowered her leather sock into the well, drew up some water and gave the dog to drink. She was forgiven on account of this."

Islam teaches us that we should show mercy to dumb animals and small birds too. The Prophet, peace be upon him, came upon an emaciated camel and said: "Fear Allah regarding these dumb animals. Ride them when they are in good condition and feed them when they are in good condition"

A man said: "O, Messenger of Allah, I have mercy on the sheep before I slaughter it". The Prophet, peace be upon him, replied: "If you have mercy on it, Allah will have mercy on you"

The Prophet of Islam said on small birds: "Whoever kills a sparrow or anything that is greater than this without its due reason, then Allah will ask him about it on the Day of Judgment." He said:"What is its due reason, O, Messenger of Allah?" He said: "To slaughter it for the sake of eating, and avoid cutting its throat off to be thrown."

The Prophet also said: "Allah has prepared one hundred blessings (rahmat). He holds back ninety-nine and sends down to earth one. It is with that one blessing He sent down that all creatures love each other and animals lift their feet off their off-spring so as not to injure them." (Muslim)

The Prophet was especially compassionate toward children. He said:
"I stand in prayer and wish to prolong it. However, I hear a child cry and shorten the prayer to lessen the mother's anxiety." (Bukhari)
Once a man told Prophet Muhammad: "I have 10 children, none of whom I have ever kissed." God's Messenger responded: "One without pity for others is not pitied." (Bukhari)

Islam is a religion for humanity. This is clear with the following hadiths:

"People who love will be loved by Allah the most Benevolent, so love the inhabitants of this earth so that you may be loved in return by the inhabitants of the Heavens." (Abu Daud)
"He who does not love will not be loved" (Bukhari)
"Allah will not love he who does not love other human beings" (Bukhari)

The United Nations declared 1995 as the year of tolerance. It said that the ability to be tolerant of other beliefs, opinions and actions is a great contributor to world peace. It also said that racism and religious fanaticism in many countries have led to many forms of discrimination.
It is impossible to remove differences in this world so we need to be more tolerant of each other. This means that we need to learn to patient in situations where our peace is disturbed. In fact, we exhibit excellent character when we are tolerance and merciful toward others who do not hold the same views as us. When we are tolerant toward others our mental balance is upset. As such, we learn the art of self-control and as a result build character. And if day in and day out we continue to show such tolerant behavior with others for sake of Allah's pleasure, we will become closer to Him and gain His love inshallah. We need to be on our guard at all times and always reassess our behavior and criticize ourselves to become the type of people God wants us to be.

Our most merciful Lord says:

Lo! those who believe and do good works,
the Beneficent will appoint for them LOVE. [Maryam (19)096]

Without love and mercy, there will be chaos in society. Showing mercy to Allah's creatures creates a society of peace and tolerance. Every Muslim must show great compassion to others. He should pray for Non-Muslims to be guided and wish them well. Prophet Muhammad's greatest concern during his mission was for everyone to become rightly guided:

Yet it may be, if they believe not in this Message, you will consume (exhaust) yourself, following after them, with grief. [Al-Kahf 18:6]

When the Prophet was wounded at the battle of Uhud, he prayed to God by saying:

"O God, forgive my people, for they do not know."

However, Muslims are not to tolerate those who are infidels and deny the truth consistently. Those who persisted on oppression and persecution and wanted to destroy the Prophet and his followers were not dealt with tolerantly. The believers had to fight such people. Personalities like Abu Jahl and Abu Lahb were not tolerated.

O ye who believe! Choose not My
enemy and your enemy for allies. Do ye give them friendship
when they disbelieve in that truth which hath come unto
you, driving out the messenger and you because ye believe
in Allah, your Lord? If ye have come forth to strive in My way
and seeking My good pleasure, (show them not friendship).
Do ye show friendship unto them in secret, when I am Best
Aware of what ye hide and what ye proclaim? And whosoever
doeth it among you, he verily hath strayed from the right
way. [Al Mumtahanah (60)001]

Muslims' attitude toward unbelievers is a form of pity. Once when Umar (may Allah be pleased with him) saw an 80 year old unbeliever he sat down and cried. He said: "God assigned him so long a lifespan, but he has not been able to find the true path."
When the Prophet was asked to curse on disbelievers, he refused and said:

"I was not sent to call down curses on people, but as a mercy."

Allah SWT knows best.