Question: Oh Virtuous Shaikh, we are facing the last ten days of Ramadan after the ten middle days/nights of the month. What is your advice, May Allah facilitate for you [good], specifically for those making ‘Itikaaf. Many people making ‘Itikaaf ask about what time to start the ‘Itikaaf and when to exit ‘Itikaaf? Is it from the Sunnah not to leave for Eid prayer that day? Is it from the Sunnah for the one in ‘Itikaaf to make ghusl after the maghrib prayer every night of the ten nights?
Answer: “The last ten days are without doubt the best days of Ramadan because in them is the Layl-tul-Qadr either on the twenty-first or twenty-third or twenty-fifth or twenty-seventh or twenty- ninth of the month. These times are more emphasized. It is possible for it to be the twenty- second or twenty-fourth or twenty-sixth or twenty-eighth and the thirtieth. The most emphasized time is the twenty seventh. However in general, it is not specified with something [of worship] except emphasis on standing for prayer due to the Prophet(ﷺ) statement:
من قام ليلة القدر إيماناً واحتساباً غفر الله له ما تقدم من ذنبه
Whosoever performs Qiyam during Lailat-ul-Qadr (Night of Decree), with Faith and being hopeful of Allah’s reward, will have his former sins forgiven
[Al-Bukhari and Muslim]
As for what some people do of increased charity on the twenty seventh night claiming it to be Layl-tul Qadr or making Umrah on the twenty seventh night claiming it to be Layl-tul Qadr, then this is a mistake from two angles:
First: the twenty seventh is not Layl-tul Qadr because Layl-tul Qadr occurred in the time of the Prophet (ﷺ) on the night of the twenty first.
Second: If it is established that it is Layl-tul Qadr and it is not established except by the witnessing of associated conditions [signs], however, it can not be certain. Then it is not specified [with worship] except with what the Legislator specified and it is standing for prayer. Charity in that night does not have an increased reward and Umrah does not have an increased reward. This is an important issue.
As for the issue of ‘Itikaaf, then a person enters ‘Itikaaf when the sunsets on the day of twentieth, that is: the beginning of the twenty-first. It ends at the setting of the sun on the last day of Ramadan whether it be the twenty-ninth or thirty. He leaves to his house and there is no need to remain in the masjid until he leaves to the Eid prayer. So this has no evidence even though some scholars say this.
Also: the one in ‘Itikaaf leaves like other than him with the most beautiful and best clothing. It is not like some people say: he leaves with the clothing that he is wearing and they claim it is a trace of worship, like blood remaining on the martyr. We say: clothing is not a trace of ‘Itikaaf because ‘Itikaaf is not distinguished by clothing.
Likewise, it is necessary for the one in ‘Itikaaf as long as he is in ‘Itikaaf and imprisons himself in the masjid, to pass his time in the obedience of Allah azza wa Jal from reading Quran and remembering Allah and prayer in other than the prohibited times and other than that of actions that draw near to Allah. He should not make this place, I mean the masjid, a shrine which his friends visit and relatives and they go from speech to speech and from coffee to coffee (and sometimes from sunflower seeds to sunflower seeds) and what resembles that.This is a mistake. ‘Itikaaf is to worship Allah by remaining in the masjid for the obedience of Allah. I ask Allah to give us and you a share [of reward] from this month and from Layltul Qadr a share and to use us in his obedience and protect us from disobedience.
Making ghusl after maghrib is not a Sunnah. What is well-known from the Salaf in terms of showering [after maghrib on the last ten nights] was for them to become invigorated for standing in prayer. Its intent was not for itself. Based on that: in the days of winter a person does not need energizing because there is less laziness when its cold. Also in regards to the days of winter in our times, there are stimulants other than showering like: coffee, tea, juice and what resembles that”.
[Taken from: http://shamela.ws/browse.php/book-7686/page-2072 ]
Faisal Ibn Abdul Qaadir Ibn Hassan