From Jareer bin Abdullaah -Radi Allaahu anhu- who said: the Messenger of Allaah -sallAllaahu alayhi wa sallam- said:
‘Whoever does not have mercy upon the people then Allaah does not have mercy upon him.’ Collected by Bukhari & Muslim
Shaykh AbdurRahman bin Nasr as-Sa’adi (d. 1376 A.H.) commented on this hadeeth saying:
‘The literal wording of the hadeeth indicates that the one who does not have mercy upon the people then Allaah does not have mercy upon him. The understanding of the hadeeth is that whoever has mercy upon the people, then Allaah has mercy upon him.
Just like the Messenger -sallAllaahu alayhi wa sallam- said in another hadeeth:
‘ar-Rahman (The Most Merciful) has mercy upon Merciful people. Have mercy upon those on the earth, and the One above the skies will have mercy upon you.’
Therefore, the mercy a slave of Allaah has for the creation is from the greatest means by which the mercy of Allaah is acquired. From the effects of that mercy is goodness in the Dunyaa and goodness in the Hereafter. From the greatest means of Allaah’s mercy being blocked and prevented is if the slave of Allaah does not have mercy to the creation. The slave of Allaah is in great need and dire want of Allaah’s mercy, he cannot do without it for even the blink of an eye, and he cannot do without this mercy due to what it contains of blessings and repelling of punishment from the mercy of Allaah.
Consequently, when a person wants the mercy of Allaah to continue and increase, then he needs to implement all the means by which the mercy of Allaah is gained. All of these means are combined in the saying of Allaah Ta’ala:
They are doers of good (al-Muhsinoon) in the worship of Allaah, and they are al-Muhsinoon to the worshippers of Allaah. The Ihsaan (being good) to the creation has an effect from the effects of the mercy that the slave of Allaah has with the creation.
There are two types of mercy that the slave of Allaah has:
The First type: Natural & innate mercy
Allaah has granted some of His slaves this mercy. He placed compassion, mercy and sympathy in their hearts for the creation. These slaves of Allaah carryout what they are capable of in benefitting the people and this is what this mercy necessitates and they do so according to their capabilities. They are praised, and rewarded for what they do, and they are excused for that in which they fall short on, and perhaps Allaah wrote a reward for them, due to their truthful intentions even though their strength was not enough to carry out those actions.
The Second type is the mercy that a slave of Allaah acquires by following every path and means in order to characterize his heart with this mercy. The slave of Allaah knows that this description is from the most noble and most complete of manners and behavior. He strives to characterize himself with it, and he is aware of the reward that Allaah has prepared for being merciful, and what he loses, if he is prohibited from this reward. He desires excellence from his Lord, and he strives with all the different means to acquire that excellence.
The slave of Allaah knows that the reward is equivalent to the type of action carried out, and he knows that Allaah has ordained a religious brotherhood, and a love based on Eemaan between the Believers. Allaah ordered the believers to be brothers loving each other, and to eliminate everything that negates brotherhood from hatred, enmity and evil plotting.
The slave of Allaah continues to be acquainted with the means by which he acquires this noble characteristic of being merciful, and he exerts himself in implementing this characteristic so much so that he fills his heart up with this mercy, and sympathy for the creation. How great is this noble manner, and noble and complete characteristic.
The effects of this mercy, which is in the hearts, becomes evident upon the limbs and the tongue in striving to do good, righteousness and relaying benefits to the people, and to discontinue harm, and being compelling and offensive to the people.
The sign that shows the presence of mercy in the heart of the slave of Allaah is that he loves that goodness reaches all of the creation generally, and specifically to the Muslims, and he dislikes that evil and harm reaches them. And will be in relation to the level of love and dislike he has, and will be in relation to the level of mercy that he has.
Whoever is afflicted by the death of a beloved person or by other afflictions, and if his sadness upon that person or affliction is due to feeling merciful, then this sadness is praiseworthy, and it does not negate patience and seeking Allaah’s pleasure, this is because when the Messenger -sallAllaahu alayhi wa sallam- cried due to the death of his grandson, Sa’ad said to him: ‘What is this O Messenger of Allaah?’
The Messenger -sallAllaahu alayhi wa sallam- followed up his question with another statement and said:
‘This is mercy, which Allaah places in the hearts of His slaves. Indeed those whom Allaah has mercy upon from His slaves are those who are merciful.’ [Collected by Bukhari & Muslim]
And likewise the Messenger -sallAllaahu alayhi wa sallam- said at the death of his son Ibraheem:
‘The heart is saddened, the eyes shed tears, but we only say that which pleases our Lord. And indeed we are saddened by your separation O Ibraheem.’ [Collected by Bukhari & Muslim]
Likewise having mercy upon young children and slaves, and making them happy is also from being merciful¬.
As for not having concern for them and not having gentleness with them, then this is from coarseness, harshness and cruelty, just like some of the coarseness of the Bedouins when they saw the Prophet -sallAllaahu alayhi wa sallam- and his companions kissing their younger children, one of the Bedouins said:
‘I have ten children I did not even kiss one of them.’
The Prophet -sallAllaahu alayhi wa sallam- said:
‘How can I hold something for you, with Allaah has removed mercy from your heart?’
Also, an example of being merciful is the mercy that the prostitute had when she gave water to a dog to drink, he was going to eat dirt due to extreme thirst, and Allaah forgave her due to that mercy.
The opposite of that example is how a woman was punished due to her tying up a cat, she did not feed her or give her drink, nor did she leave her to eat from the leftovers on the earth, until that cat died.
Additionally from this mercy is that which has been witnessed and experienced, and that is that whoever is kind to his animals by giving them food and drink and beneficial consideration, then Allaah blesses him regarding his animals, and whoever is evil to them, then he is punished in the Dunya before the Hereafter.
Allaah Ta’ala said:
This is because the first heart has cruelty, harshness and evil, whereas the other heart has mercy and gentleness and compassion, and he is concerned with reviving all those people from whom he has the ability to revive, in comparison to the first heart which has cruelty, and is prepared to annihilate all the people.
We ask Allaah to place mercy in our hearts which will obligate us to follow all the ways that gain the mercy of Allaah, and that we sympathize with all the creation of Allaah due to this mercy. And that Allaah makes it a way of gaining Allaah’s mercy and His generosity; indeed He is the Bestower of goodness and the Most Kind.
[Taken from: ‘Bahtaja al-Qaloob al-Abraar wa Qarat Ayoon al-Akhbar’- Imaam as-Sa’adi p. 365 no.82]
 Collected by al-Humaidi in ‘al-Musnad’, Ibn Abee Shaybah in ‘al-Musanaf’, Ahmad, al-Marwazi in ‘al-Birr wa Silaah’, Darmi in ‘ar-Radd ala Jahmeeyah’, Bukhari in ‘Tareekh al-Kabeer’, Abu Dawood & Tirmidhi and many other scholars.
It was authenticated by Tirmidhi, Hakim in ‘al-Mustadrak’ & Dhahabi agreed with him, Albaani in ‘Silsilah al-Ahadeeth as-Saheehah’ No. 925, & many other scholars.
Al-Imam Ishaq bin Rahawayyah (d.238 A.H.) said:
‘Allaah Ta’ala said: [Taha: 5]. There is a consensus (Ijmaa) of the people of knowledge that Allaah is Mustawaa’ (ascended) above the ‘Arsh (Throne), and He knows every single thing under the seven earths.’
Ad-Dhahabi commented on this statement in ‘al-‘Aloo’:
‘Listen –and turn – to this Imam and how this Imam conveyed a consensus of this noble issue, just like Qutaibah conveyed this consensus in his time.’
Qutaibah bin Sa’eed (d.240 A.H.) said:
‘The statement of the Imams of Islaam, the Sunnah and the Jammaah is that we know that our Lord is above the sevens, above His ‘Arsh (Throne), like He said: [Taha: 5]
Ad-Dhahabi commented on this statement in ‘al-‘Uloo’:
‘So this is Qutaibah, being a great trustworthy Imam, who conveyed a consensus of this issue. He had met Malik, Layth, Hammad bin Zayd, the senior scholars and he lived a long life and the memorizers of hadeeth used to crowd around at his door.’
[Taken from: footnotes from: ‘Bahtaja al-Qaloob al-Abraar wa Qarat Ayoon al-Akhbar’- Imaam as-Sa’adi p. 365 no.82]
 [Collected by Bukhari & Muslim from the hadeeth of Aeysha -Radi Allaahu anha]
 [Collected by Bukhari & Muslim from the hadeeth of Abu Huriarah -Radi Allaahu anhu]
 [Collected by Bukhari & Muslim from the hadeeth of Abdullaah bin Umar -Radi Allaahu anhu]