My friend neither wears the Hijaab nor observes the obligatory prayers. Seeking the help of Allaah The Almighty, I am trying to convince her that both prayer and the Hijaab are among the obligations of a Muslim woman. Hoping that this may be the beginning of a new phase in her life and a cause for the guidance of Allaah, I am trying to take her with me to the mosque to attend religious lectures and listen to the Friday sermon. However, she fears wearing the Hijaab only while attending religious lectures in the mosque, then taking it off. Likewise, she fears performing the Friday prayer only and then ceasing to pray. In her case, is it permissible to wear the Hijaab with the intention of attending these religious lectures? Is it permissible for her to perform the Friday prayer only? If she does not pray at all, is it permissible for me to be in her company?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger. 

Non-adherence to the Hijab (Islamic covering) is a  prohibited evil deed. Wearing the Hijab is an obligation upon every Muslim woman. Allaah The Almighty Says (what means): {O Prophet, tell your wives and your daughters and the women of the believers to bring down over themselves [part] of their outer garments.} [Quran 33: 59]

The evil that is greater, more prohibited and deserving of a more severe punishment, is giving up prayer. It was narrated that the Prophet, sallallaahu ‘alayhi wa sallam, said that giving up prayer is a sign of polytheism and disbelief. [Muslim] In another Hadeeth, he said that observing prayer provides guarantee and safety from disbelief, even if performed out of hypocrisy, and that whoever gives up prayer is considered one of the disbelievers and is subject to their rulings. [Ahmad] 

Consequently, may Allaah reward you and add this to the record of your good deeds. You must try your utmost to rescue your sister. In doing so, you have to be patient and seek the help of Allaah The Almighty in everything you do. We wish to remind you of the Hadeeth in which the Prophet,  sallallaahu ‘alayhi wa sallam, said that whomever Allaah The Almighty made a cause for guiding only one person to follow the teachings of Islam, this would be better for him than the best of this life's possessions.  Another narration reads: “this would be better for him than this life and all that is in it.” [Al-Bukhari and Muslim] 

As long as your friend accompanies righteous people, this means that she is inherently good. You have to continue to offer her advice and give her Da’wah using wisdom and good preaching. It is also wise to adopt a gradual approach and to encourage her to perform prayer, as it is the cornerstone of the religion and the foundation of Islam. You should also welcome any good deed that she does, praise her for it and encourage her to repeat it. Gradation is one of the norms and ways of Allaah The Almighty in the universe. It is also one of the means that the Prophet, sallallaahu ‘alayhi wa sallam, used to deliver his message.

Therefore, encourage her to attend religious lectures in the mosque and Friday sermons, in the hope that she will listen to advice that benefits her and paves the way for you into her heart.  

Even if you do this gradually, the most crucial factor is to convince her to observe prayers, wear the Hijab and adhere to the teachings of the Sharee'ah (Islamic law). Once she tastes the sweetness of faith and the pleasure of obedience, she will never return to her previous state of ignorance. We advise you not to desert her unless you have tried your utmost to guide her and despair that she will never accept the truth.

Finally, we would like to remind you of the fact that covering all of a woman's body (except the face and hands) is a prerequisite for the validity of prayer.

Allaah Knows best.