Firstly, the concept of having gatherings wherein the blessed mention of RasulullahSallallahu Alaihi Wa Sallam is made is indeed a praiseworthy one. None can deny that it is an act of virtue to reminisce about the noble Seerah of RasulullahSallallahu Alaihi Wa Sallam. Therefore, there is no problem with a Seerah Jalsah being held at any time during the year. Similarly, the issue of Mawlid falls under the ambit of discussing the blessed life of RasulullahSallallahu Alaihi Wa Sallam.
The truth of the matter is that there is not a single moment, neither any month of the year, nor any day of the month, nor any hour of the day, nor any second of the hour, where extolling the praises of the Messenger Sallallahu Alaihi Wa Sallam or speaking about his life, is impermissible. This issue is no point of contention. The point of contention is with specifying a date to hold a Mawlid gathering annually. Especially, when the date 12th of Rabi ul Awwal being the birthdate of RasulullahSallallahu Alaihi Wa Sallam is based on weak evidence. The scholars differ on the birthdate of Rasulullah Sallallahu Alaihi Wa Sallam. The most correct opinion is that it was most likely on the 8th of Rabi ul Awwal.
The first person who initiated the practice of Meeladun NabiSallallahu Alaihi Wa Sallam was one of the Oppressive kings of the Fatimid Empire around the fourth century Hijri. If one were to study their Aqeedahs (beliefs), it would become clear as daylight that they were not even Muslims. During the time of the Salafus Saliheen (pious predecessors) and Khair ul Quroon, love and affection for Nabi Sallallahu Alaihi Wa Sallam was perfect. They had profound and extreme love and affection, yet they did not hold a gathering to celebrate the birth of Nabi Sallallahu Alaihi Wa Sallam. Who is there that can exceed them in respecting and honouring NabiSallallahu Alaihi Wa Sallam? No such narration ever reached us through any chain of narration that Nabi Sallallahu Alaihi Wa Sallam, the Sahabah, the Tabi’een or the Tabi’ Tabieen ever held such a gathering. If any of them ever celebrated Meelad Nabi on a large scale, most definitely there would be many narrations that would have reached us.
The position of the Deobandi Ulama is that, not only is it permissible to have a gathering of Mawlid, rather it is an act of great virtue, as long as the gathering is free from the unlawful or reprehensible activities, such as free intermingling of the sexes, excessive wasteful spending, adding conditions to it e.g. specifying a particular date, etc., and it is not understood to be something necessary to such an extent that those who choose not to participate are considered to be in the wrong or are looked down upon.
The above is understood from Al-Muhannad ‘Ala Al-Mufannad by Hadhrat Moulana Khalil Ahmad Saharanpuri Rahimahullah which reflects the beliefs and stances of the Ulama of Deoband. Hereunder is the excerpt in reference: A translation of the relevant parts is as follows: “Far be it from any Muslim that he says (let alone us), mentioning the birth of the Messenger of Allah Sallallahu Alaihi Wa Sallam or even mentioning the soil under his footwear and the urine of his donkey, is an act of reprehensible and unlawful innovation. Thus, aspects that have even a slight connection with the Messenger of Allah Sallallahu Alaihi Wa Sallam, mentioning them is from the much-loved of practices and from the greatest of recommendations, be it the mention of his blessed birth, or the mention of him relieving himself, his standing, his sitting, his sleeping and him being awake. This has been explained in detail in my book al-Barahin al-Qati’a in many places.” ……..“ It is clear from the above that we do not reject the mentioning of the Messenger Sallallahu Alaihi Wa Sallam of Allah’s birth; rather, we reject and refute those evils that are attached to such gatherings as you have them in the Indian subcontinent, such as mentioning fabricated and false narrations, intermingling of the sexes, excessive wasteful spending with lights and decorations, holding it to be something necessary to do such that those who choose not to participate are slandered and called non-believers, and other evils from which very few gatherings (in the subcontinent) are free. However, if the gathering is free from such evils, far be it from us that we say, mentioning the birth of the Messenger of Allah Sallallahu Alaihi Wa Sallam is an evil and an innovation…” This much should be remembered that the occasion and gathering of Mawlid which are generally in vogue nowadays is one thing; and extolling, lauding and speaking about Nabi Sallallahu Alaihi Wa Sallam is another. The former is a Bid’ah whereas the latter is praiseworthy and Mustahab. In this regard Maulana Rashid Ahmed Gangohi Saheb Sallallahu Alaihi Wa Sallam [passed away 1323 AH] said, ‘the actual extolling of Wilaadat (birth of Nabi Sallallahu Alaihi Wa Sallam) is praiseworthy. It will become Makrooh if conditions/restrictions are attached to it.’ [Fataawah Rashidiyyah, vol.1 page 102] He further states, ‘It is Mustahab to extol the Wilaadat (birth) of NabiSallallahu Alaihi Wa Sallam however due to the attachment of various conditions/restrictions, this gathering is now prohibited.’ [vol. 1 page 110]
If an intellectual person cannot understand the difference between the simple extolling of Wilaadat and the gatherings of Mawlid that are in vogue nowadays, then we have no cure for him. It is evident that the people of the past did not carry out the Mawlid as is in vogue today by confining it to a particular date, mentioning only the birth events instead of the full Seerah of RasulullahSallallahu Alaihi Wa Sallam, narrating mostly fabricated narrations, undue extravagance, deeming it a necessity of Deen, and looking down upon those who do not participate. And if someone in the past did conduct Mawlid in an incorrect manner like was done by Sultan Muzaffar ud Deen (d. 630 A.H.), the Ulema of Haqq always spoke out against it. We can therefore conclude that if one were to carry out Mawlid free from such evils, then it is permissible to do so. However, the fact of the matter is that Mawlid today, especially in the Indian subcontinent, is more or less always accompanied with the aforementioned evils and this renders it impermissible to attend and carry out. For further information, one may refer to the following article, translated from the writings of Moulana Ashraf Ali Tahnwi Rahimahullah
https://www.deoband.org/2010/02/fiqh/miscellaneous/mawlid-deoband-and-hanafi-fiqh/
There were Ulama who granted permission in the past. However, if they were alive today to see the amount of wrongs that takes place in the gatherings of Mawlid that are in vogue in modern times, we have no doubt that they would also discourage the people from attending it just like the illustrious elders of Deoband did.