The Anti Ahmadis have sadly placed the constitution of Pakistan above the law of Allah and have many times stated that you are kaffirs because the law of constitution says this. This statement itself shows their ignorance. According to the Ahadith it is clear that Ahmadis are not only Muslims, but in reality the true followers of the Prophet(saw).
The Holy Prophet(saw) states:
Narrated Anas bin Malik: Allah’s Messenger (ﷺ) said, “Whoever prays like us and faces our Qibla and eats our slaughtered animals is a Muslim and is under Allah’s and His Apostle’s protection. So do not betray Allah by betraying those who are in His protection.”(Sahih Bukhari, Volume 1, Book 8, Hadith #386)
I also suggest the anti Ahmadis be careful when declaring the true Muslims as disbelievers as The Prophet(saw) also stated:
The Prophet (ﷺ) said, “Whoever swears by a religion other than Islam, is, as he says; and whoever commits suicide with something, will be punished with the same thing in the (Hell) Fire; and cursing a believer is like murdering him; and whoever accuses a believer of disbelief, then it is as if he had killed him.”(Sahih Bukhari, Volume 8, Book 78, Hadith #647)
Now when we come to the issue of the Pakistani constitution it causes a lot of confusion. On one hand 73 sects get together to declare one true jamaah of Allah as disbelievers, not realizing that within themselves they have already declared each other kaffir.
For example according to the Barelvi leader Ahmad Raza Khan, both Wahabbi and Deobandi are kafirs (Khan, Ahmad Raza, Hisam Al Haramain, pages 100 and 113)
In fact 300 scholars of the sunni Ulama are stated to:
“‘have given this fatwa unanimously that the Wahabbia/ Deobandi sects are among extreme apostates and infidels. Indeed they are infidels of such hue that any one who does not regard them as infidels is also counted among the infidels and his wife will become automatically divorced in such a situation. Any progeny from such a marriage will be illegitimate and can claim no inheritance under Muslim law” (Ibrahim Muhammad, Unanimous Fatwa of Three Hundred Ulama)
Some Muslim divines have stated in regards to the Wahabbis and Deobandis:
“‘They stand condemned as the worst and most dangerous, far more dangerous than idolaters and maggians.”(Akhram a Shariat Mukamal, Abhoh al Muzanb, Parts 1 and 14)
For the ones who belong to Jamaat-e-Islamic it is stated in regards to them :
“‘There is no doubt that he is amongst those who have been led astray. I strongly urge Muslims to keep themselves aloof from his beliefs and ideology. They should not regard him a servant of Islam and should not be under any illusions. The Holy Prophetsa declared that before the appearance of the Dadjaal, thirty other Dadjaals would be born to pave the way for him. As I understand it, Maududi is one of these thirty dajjals” (Siddiq Maulvi Muhammad, Haq Parast Ulema Ko Maudidat say Narazghi ke Asbab)
Now when we look at the Barelvis, there are fatwas against them as well. Maulvi Sayyid Muhammad Murtaza who belongs to the Deobandis declared Ahmad Raza Khan to be a murtad a dajjal of the century and a great kafir who is outside the pale of Islam (Murtaza Maulvi Sayyid Muhammad, Radd at Takfir ala I Fahash Al Tanzir)
It is clear that many sects believe each other to be kaffirs so this is not a valid argument against jamaat. The Holy Prophet(saw) prophesied that:
Narrated ‘Abdullah bin ‘Amr: that the Messenger of Allah (ﷺ) said: “What befell the children of Isra’il will befall my Ummah, step by step, such that if there was one who had intercourse with his mother in the open, then there would be someone from my Ummah who would do that. Indeed the children of Isra’il split into seventy-two sects, and my Ummah will split into seventy-three sects. All of them are in the Fire Except one sect.” He said: “And which is it O Messenger of Allah?” He said: “What I am upon and my Companions.(Jami’at Tirmidhi #2641)
Allah made it Clear in regard to who this Jamaah was in the Pakistani newspaper where it stated: “Throughout the history of Islam, such an overwhelming complete consensus has never been reached on any important topic… “Excluding Qadianis (A term used for Ahmadis by other Muslims) all the rest of 72 sects which are considered to be Muslims, agreed and are happy on the solution of this affair” (Editorial published in Urdu In Pakistani Daily Newspaper “Nawai Waqt” , 10th Oct 1974)