No punishment for takfir with false taweel
Shaykh ul Islaam Ibn Taymiyyah [ra]
Majmoo' il Fataawa Vol 3, 283-284
If a Muslim is incorrect in his understanding about killing [a Muslim] or making "takfir" [of a Muslim], then he does not become a [major] disbeliever because of that [mistaken understanding of his], this is like when Umar Ibn al Khattaab [ra] said about Haatib ibn Abi Balta' [ ra], "Oh RasulAllah [saw]! Allow me to behead this hypocrite! RasulAllah [saw] replied, " Indeed, he is one who witnessed [participated in the battle of] Badr. And you do not know if Allah [awj] has looked towards the people of Badr and said to them " Do as you like, for you have been forgiven. " And this [hadeeth] in found in the two Saheeh collections.[ Bukhari Maghazi 46 & Muslim Fadailu's-sahaba 161]
And in them is also found the narrations of "al-Ifk": Usayd ibn Hudayr [ra] said about Sa'd ibn Ubaadah, [ra]; " Indeed, you are a hypocrite, arguing [on behalf of] the hypocrites." So the two parties (Aws and Hazraj) began to argue, so RasulAlla [saw] make peace between them." [Bukhari Shahadat 15; Magazi 34 & Muslim Tawba 56]
These [the Companions mentioned in this hadeeth] were all participants in Badr and from them was the one who said, "You are a hypocrite.", [and yet] RasulAllah [saw] did not call him a disbeliever, nor the other, but rather he bore witness that all of them will be in paradise.
And similarly to this is what is authentically established in the two saheeh collections regarding Usaamah ibn Zayd [ra]. He killed a man after he [the person he killed] said "There is nothing worthy of worship except Allah", and RasulAllah [saw] severly reprimanded him when he heard about it and said to him, " Oh Usaamah! Did you kill him after he said there is nothing worthy of worship except Allah? " and he [saw] kept on repeating this question to Usaamah [ra] until Usaamah [ra] said, " I wished that I had not accepted Islam until that day" [Bukhari diyat 2 & Muslim Tawba 159]
And along with this, he, [saw], did not seek any retribution [from Usaamah] nor blood, nor expiation from him, because he was mistaken [in his belief about killing that man], thinking that that man only said those words [of tawheed] to protect himself [from Usaamah's sword]. "
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