Umar was heard to say, "Anyone who does not show mercy will not be shown mercy. Anyone who does not forgive will not be forgiven. Anyone who does not turn in repentance will not be turned to nor will he be protected or guarded."

Mu'awiya ibn Qurra reported that his father said, "A man said, 'Messenger of Allah, I was going to slaughter a sheep and then I felt sorry for it (or 'sorry for the sheep I was going to slaughter').' He said twice, 'Since you showed mercy to the sheep, Allah will show mercy to you.'"

Abu Hurayra said, "I heard the Prophet (ﷺ) the truthful confirmed one, Abu 'l-Qasim, may Allah bless him and grant him peace, say, 'Mercy is only removed from the one who is destined for wretchedness."

Jarir reported that the Prophet (ﷺ) said, "Allah will not show mercy to a person who does not show mercy to other people."

Anas ibn Malik said, "The Prophet (ﷺ) was the most merciful of people towards members of his family. He had his son (Ibrahim) suckled in part of Madina and the husband of his wet-nurse was a blacksmith. We used to go to him and the house would be full of smoke from the bellows. He would kiss the child and take him in his lap."

Abu Hurayra reported that the Messenger of Allah (ﷺ) said, "One day a man became very thirsty while walking down the road. He came across a well, went down into it, and drank and then climbed out. In front of him he found a dog panting, eating the dust out of thirst. The man said, 'This dog is as thirsty as I was.' He went back down into the well and filled his shoe, putting it into his mouth (in order to climb back up) and then gave the dog water. Therefore Allah thanked him and forgave him." They said, "Messenger of Allah, will we have a reward on account of animals?" He said, "There is a reward on account of every living thing."

You did not feed it nor give it water when you imprisoned it nor did you release it and let it eat from the plants of the earth."

Abdullah ibn al-'As reported that the Prophet (ﷺ) said, "Show mercy and you will be shown mercy. Forgive and Allah will forgive you. Woe to the vessels that catch words (i.e. the ears). Woe to those who persist and consciously continue in what they are doing."

Abu Umama that the Messenger of Allah (ﷺ) said, "Anyone who shows mercy, even to an animal meant for slaughtering, will be shown mercy by Allah on the Day of Rising."