The fasting that is prescribed in Rajab is the same as that prescribed in other months, namely fasting on Mondays and Thursdays, and the three days of al-Beed, fasting alternate days, and fasting Sirar al-Shahr.
Some of the scholars say Sirar al-Shahr refers to the beginning of the month; others said that it refers to the middle or end of the month. ‘Umar (as) used to forbid fasting in Rajab because it involved resemblance to the Jahiliyyah. It was reported that Kharashah ibn al-Harr said: I saw ‘Umar smacking the hands of those who fasted in Rajab until they reached out for food, and he was saying:” This is a month which was venerated in the Jahiliyyah.” (Al-Irwaa’, 957; al-Albani said: it is saheeh).
Imam Ibn al-Qayyim said: the Prophet (pbuh) did not fast for three consecutive months (i.e., Rajab, Sha’ban and Ramadan) as some people do, and he never fasted Rajab at all, nor did he encourage people to fast this month.
Al-Hafiz ibn Hajar said in Tabayyun al-‘Ajab bima wurida fi Fadl Rajab:
No saheeh hadeth that may be used as evidence has been narrated concerning the virtues of the month of Rajab or fasting this month or fasting in any specific part of it, or observing Qiyaam al-Layl specifically during this month. Imam Abu Isma’el al-Harawi al-Hafiz has already stated this before me, and we have narrated this from others also.
In Fatawa al-Lajnah al-Da’imah it states: with regard to fasting specifically in Rajab, we do not know of any basis in Sharee’ah for doing that.
Umrah in Rajab
The ahadeth indicates that the Prophet (pbuh) did not do ‘Umrah during Rajab, as it was narrated that Mujahid said: ‘Urwah ibn al-Zubayr and I entered the mosque, and there was ‘Abd-Allah ibn ‘Umar sitting near the room of A’ishah (as). He was asked: “How many times did the Messenger of Allah (pbuh) do ‘Umrah?” He said, “Four times, and one of them was in Rajab.” We did not want to argue with him. We could hear A’ishah Umm al-Mu’minen brushing her teeth (i.e., the sound of the miswaak) in her room. ‘Urwah said, “O Mother of the Believers, did you not hear what Abu ‘Abd al-Rahman is saying?” She said, “What is he saying?” He said, “He is saying that the Messenger of Allaah (pbuh) did Umrah four times, one of them in Rajab.” She said, “May Allah have mercy on Abu ‘Abd al-Rahmaan, (the Prophet (pbuh)] never did ‘Umrah but he witnesses it (i.e., he was present with him), and he never did ‘Umrah during Rajab.” (Agreed upon).
It was reported by Muslim that Ibn ‘Umar heard this and did not say yes or no. Al-Nawawi said: the fact that Ibn ‘Umar remained silent when A’ishah denied what he said indicates that he was confused, or had forgotten, or was uncertain. Hence it is an innovated bid’ah to single out Rajab for making Umrah and to believe that doing Umrah in Rajab has a specific virtue. Nothing to that effect has been narrated, besides the fact that the Prophet (pbuh) is not reported to have made Umrah during Rajab at all.
Shaykh ‘Ali ibn Ibrahem al-‘Attar (d. 724 AH) said: One of the things that I have heard about the people of Makkah – may Allah increase it in honour – is that they do Umrah frequently during Rajab. This is something for which I know of no basis, all I know is that it was reported in the hadeth that the Messenger of Allah (peace and blessings of Allah be upon him) said: ” Umrah in Ramadan is equivalent to Hajj.”
Shaykh Muhammad ibn Ibrahem (may Allah have mercy on him) said in his Fatawa: As for singling out some of the days of Rajab for any kind of good deed, ziyarah (visiting the House of Allah, the Ka’abah) or anything else, there is no basis for this, because Imam Abu Shamah stated in his book, al-Bida’ wa’l-Hawadith: specifying acts of worship at times that were not specified by shari’ah is wrong; no time is to be regarded as better than any other except in cases where the shari’ah gave preference to a certain act of worship at a certain time, or stated that any good deed done at this time is better than good deeds done at other times. Hence the scholars denounced the practice of singling out the month of Rajab for doing Umrah frequently.
But if a person goes for Umrah during Rajab without believing that this has any particular virtue and because it is just a coincidence, that it is easier for him to go at this time, then there is nothing wrong with that.
source : allafrica.com