There is a narration according to which some of the companions of the Holy Prophet (S) brought gifts for the daughter of the Prophet (S), Lady Fatima Zahra (S.A) on her wedding ceremony. Abdur Rahman was also amongst them. Like many other companions, he also gave Imam Ali and Fatima Zahra, peace be upon them, a gift on their wedding. Before mentioning and elaborating on the narration, it is necessary to note the following:
1. There is no doubt that celebrating a wedding, and expressing joy and happiness are rational and were allowed on happy occasions such as a wedding even during the time of the Holy Prophet(S) and the Infallible Imams (A.S).[1]  Today, such occasions and customs are in place and there is no objection to them. In fact, what makes something to be disallowed and become haram is to engage in a sinful act. Such allowable practices could become haram, if they involve committing sins.
2. Giving gifts is also good and recommended by reason and religion and there are numerous historical instances which clearly indicate that gifts have been given on such occasions.[2]
Keeping the above introductory explanation into consideration, we shall now go to the main point:
"…Sa'ad bin Ma'az also brought ten sheep, Sa'ad bin Rabi came and he also brought with him ten sheep. Sa'ad bin Kheithama brought two camels and Abu Ayyub Ansari brought a sheep with a hundredweight (kharwar) of dates. Kharija bin Zaid brought a camel, a cow and four sheep. Abdur Rahman bin 'Awf came up and brought a hundredweight of dates. Uthman bin Affan came and brought with him five hundredweights of dates and twenty sheep. Each of the companions brought with him a gift and there were many gifts piled up.  The Messenger of Allah (S) accepted the gifts and gave also something in exchange but he would not accept any charity from the companions. The Messenger of Allah ordered the available wheat to be brought and he gave each companion a portion of it. They received the wheat, ground and cooked it. Thereupon, he addressed Ali (A.S) by saying, "O Ali, tonight you and I should get busy slaughtering these cows and sheep. Ali (A.S) slaughtered the sheep, skinned them and the Messenger of Allah (S) cut the meat into small pieces. They were busy doing this until sunrise and they finished the task upon sunrise. Later on Ali (A.S) said: "I did not a stain of blood on the Prophet's hand. The Messenger of Allah sent someone to invite the companions and said: "Today is the day of wedlock and happiness. You and your servants help me make Ali's feast for the wedding. The companions came up and put caldrons on fire. Some were busy slicing the meat, some washing, some making and maintaining the fire. The Messenger of Allah (S) seeing his companions' efforts prayed and said:
"اللّهمّ اعنهم على طاعتک و لا تؤیسهم من رحمتک و لا تخلهم من فضلک"
O Allah, help these (people) in obeying You, do not disappoint them from Your blessings and do not deprive them of Your grace.
Two hours had passed and the food was ready. The Prophet (S) told Ali to inform the migrants, locals and everyone about the feast, invite men, servants and children and all to the feast and not to leave anyone uninvited in Medina…"[3]
There is no doubt that there a lot of narrations and reports regarding the story of the night of the wedding of Imam Ali (A.S) and Fatima Zahra. There is various in the reports. However, what is certain is that the practice of giving and receiving gifts in the time of the Holy Prophet (S) was common and considered to be valuable.

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