Ibn ‘Abbas reported God’s Messenger as saying, "One who seeks to take back a gift is like a dog which returns to its vomit. An evil example does not apply to us*.” * i.e. to Muslims. Bukhari transmitted it.

‘Abdallah b. ‘Amr reported God’s Messenger as saying, "None of you may take back his gift, except in the case of a father taking it from his child.” Nasa’i and Ibn Majah transmitted it.

Ibn ‘Umar and Ibn ‘Abbas reported the Prophet (ﷺ) as saying, “It is not lawful for a man to give a gift and then take it back, except a father regarding what he gives his child. One who gives a gift and then takes it back is like a dog which eats and vomits when it is full, then returns to its vomit." Abu Dawud, Tirmidhi, Nasa’i and Ibn Majah transmitted it, Tirmidhi saying it is sahih.

Abu Huraira said that a desert Arab presented God’s Messenger with a young she-camel, in return for which he gave him six young she- camels. He was displeased, and when the Prophet (ﷺ) heard that, he praised and extolled God and said, “So and so presented me with a she-camel and I gave him six young she-camels in return for it, but he was displeased. I feel inclined to accept a present only from a Qurashi, an Ansari, a Thaqafi, or a Dausi." Tirmidhi, Abu Dawud and Nasa’i transmitted it.

Jabir reported the Prophet (ﷺ) as saying, “If anyone is given a gift and has the means he should make a return for it, but if he has not the means he should express commendation, for he who expresses commendation has given thanks, he who conceals a matter has been ungrateful, and he who decks himself with what he has not been given is like him who puts on the two garments of falsehood.” Tirmidhi and Abu Dawud transmitted it.

Usama b. Zaid reported God’s Messenger as saying, “If one is done a kindness and expresses to his benefactor a desire that God may give him a good reward, he has fully expressed his commendation.” Tirmidhi transmitted it.

Abu Huraira reported God's Messenger as saying, “He who does not thank people does not thank God.” Ahmad and Tirmidhi transmitted it.

Anas said that when God’s Messenger came to Medina the Emigrants came to him and said, “Messenger of God, we have never seen people more liberal out of abundance or better in giving help when they have little than a people among whom we have settled. They have removed our trouble and shared with us their pleasant things so that we are afraid they will get the whole reward." He replied, ‘No, as long as you make supplication to God for them and express commendation of them*.” * They have no reason to fear that the Ansar will get all the reward from God so long as due expression of thanks is made. Tirmidhi transmitted it saying that it is sahih.

‘A’isha reported the Prophet (ﷺ) as saying, "Give presents to one another, for a present removes grudges.” …transmitted it. (Mirqat, 3:380 says that Tirmidhi is the source in which this tradition is found. I have looked for it with the help of the Concordance, but have been unable to find it.

Abu ‘Uthman an-Nahdi reported God’s Messenger as saying, "When one of you is given basil he must not reject it, for it has come forth from paradise.” Tirmidhi transmitted it in mursal form.

Jabir told that Bashir’s wife asked her husband* to give her son his slave and call God's Messenger as witness for her. He went to him and said, "The daughter of so and so has asked me to give her son my slave and said that I must call God’s Messenger as witness for her.” He asked whether the boy had brothers, and when he replied that he had, he asked whether he had given them all the same as he had given him. On being told that he had not, he said, "This is not good, and I will be a witness only for what is right.” * The literal translation is "Bashir's wife said: Give my son your slave.” This was presumably said to her husband. Muslim transmitted it.

Abu Huraira said that when God's Messenger was brought first fruits he saw him put them on his eyes and lips and then say, "0 God, as Thou hast shown us the first of it, show us the last of it.” He would then give them to any boys who were present. Baihaqi transmitted it in ad-Da'awat al-kabir.

He reported God’s Messenger as saying, “He who gives refuge to a stray is astray himself as long as he does not make the matter known.” Muslim transmitted it.

‘Abd ar-Rahman b. ‘Uthman at-Taimi said that God’s Messenger prohibited taking what a pilgrim has dropped. Muslim transmitted it.

Abu Sa'id al-Khudri said that ‘Ali b. Abu Talib found a dinar and after taking it to Fatima asked God’s Messenger about it. He replied that this was God’s provision, and God’s Messenger, ‘Ali and Fatima ate food which was bought with it. But afterwards a woman came crying out about the dinar and God’s Messenger said, “Pay the dinar, ‘Ali.” Abu Dawud transmitted it.

Al-Jarud reported God’s Messenger as saying, “A Muslim’s lost property is a cause of the flame of hell*.” * i.e. when the finder, wishing to keep the article, does not make public the fact that he has found it. Darimi transmitted it.

‘Iyad b. Himar reported God’s Messenger as saying, “He who finds Something should call one or two trusty people as witness and not conceal it or cover it up; then if he finds its owner he should return it to him, otherwise it is God’s property which he gives to whom He will.” Ahmad, Abu Dawud and Darimi transmitted it.

Jabir said that God’s Messenger gave licence that a man might use for himself a stick, a whip, a rope and things of that type which he picked up. Abu Dawud transmitted it.

Abu Huraira reported God’s Messenger as saying that: God is good and accepts only what is good, and He has given the same command to the believers as He has given to the Messengers, saying, “0 Messengers, eat of what is good and act righteously” (Al-Qur’an 23:51) and also, “You who believe, eat of the good things which We have provided for you” (Al-Qur’an 2:172). Then he mentioned a man who makes a long journey in a dishevelled and dusty state, who stretches out his hands to heaven saying, “My Lord, my Lord,” when his food, drink and clothing are of an unlawful nature, and he is nourished by what is unlawful, and asked how such a one could be given an answer. Muslim transmitted it.

An-Nu'man b. Bashir reported God's Messenger as saying, “What is lawful is clear and what is unlawful is clear, but between them are certain doubtful things which many people do not recognize. He who guards against doubtful things keeps his religion and his honour blameless, but he who falls into doubtful things falls into what is unlawful, just as a shepherd who pastures his animals round a preserve will soon pasture them in it. Every king has a preserve, and God’s preserve is the things He has declared unlawful. In the body there is a piece of flesh, and the whole body is sound if it is sound, but the whole body is corrupt if it is corrupt. It is the heart.” (Bukhari and Muslim.)