Is it permissible to perform Hajj on behalf of a person who does not offer Salah?

Q: My father died about fifteen years ago. He was known as a Muslim who used to observe the Sawm (Fast) of Ramadan, pay Zakah (obligatory charity) to its recipients, give in Sadaqah (voluntary charity), and do good deeds. However, he did not attend the congregational Salah (Prayer) or even the Jumu`ah (Friday) Prayer. In addition, he never performed Hajj. I am confused as I want to perform Hajj on his behalf. Is it permissible to perform Hajj on behalf of my dead father or not?

A: If you mean that your father used to abandon the congregational Salah (Part No. 10; Page No. 63) and pray individually, then he abandoned an obligatory act and committed a grave sin but it does not take him out of the fold of Islam, so you may supplicate to Allah for him and perform Hajj on his behalf. But if you mean that he never offered Salah either individually or in congregation, he then died as a non-Muslim, unless he made Tawbah (repentance to Allah) before his death, so it is not permissible to supplicate to Allah for him or perform Hajj on his behalf because abandoning Salah is tantamount to Kufr (disbelief) that takes a person out of the fold of Islam. It was reported that the Prophet (peace be upon him) said: Between a man and Shirk (associating others with Allah in His Divinity or worship) and Kufr there stands giving up Salah. (Related by Muslim in his Sahih [Book of Authentic Hadith]). Also, he (peace be upon him) was reported to have said: The covenant that stands between us and them is Salah; whoever gives it up commits Kufr. (Related by Imam Ahmad and the four compilers of Sunan [Hadith compilations classified by jurisprudential themes] through authentic Isnad [chain of narrators]) There is a lot of other proofs that support this view.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.