Can I regard her as my sister in Islam? Is it permissible for me to speak to her on the bus or in the university? Is it permissible for me to look at her face?.
Many people make the mistake of thinking that the difficulties of our times and the lack of brothers and the corrupt circumstances make it permissible to do things that may lead to their doom, and they fall into the traps of the Shaytaan.
Yes, beware of being deceived by the Shaytaan, who makes sin appear to you as obedience, and comes to you through a door which you think you have shut on him, for the Shaytaan keeps knocking at the doors of misguidance and trying to open them to the slaves of Allaah and make them fall into his traps.
Have you not heard the words of Allaah (interpretation of the meaning):
“(Iblees) said: ‘Because You have sent me astray, surely, I will sit in wait against them (human beings) on Your straight path.
17. ‘Then I will come to them from before them and behind them, from their right and from their left, and You will not find most of them as thankful ones (i.e. they will not be dutiful to You).’”
[al-A’raaf 7:16, 17]?
Ibn al-Jawzi (may Allaah have mercy on him) said in Talbees Iblees (p. 52):
Iblees tricks people in whatever way he can, and his power over them increases and decreases according to their alertness or negligence, their ignorance or knowledge.
Note that the heart is like a fortress, and the devils are always going around the fortress watching for the guards to become heedless. The guard should know all the gates of the fortress which he has been appointed to guard, and he should not let his attention slip for a moment, for the enemy never lets his attention slip.
A man said to al-Hasan al-Basri: Does Iblees sleep?
He said: If he slept, we would have a break! End quote.
The situation which you are asking about is one of the traps of the Shaytaan. How many fires have been lit in the hearts of young men, the first spark of which was a look or a smile or a meeting or a conversation, and how often does that happen under the guise of companionship, mutual advice and calling people to Allaah.
When Islam forbade free mixing between men and women, and forbade a man to be alone with a non-mahram woman, or to look at her or shake hands with her, it was paying attention to the evil consequences of such matters. Allaah is the Creator of mankind, and He knows best what is good for them and what is bad for them.
The Prophet (peace and blessings of Allaah be upon him) said: “No man is alone with a (non-mahram) woman, but the Shaytaan is the third one present.” Narrated by al-Tirmidhi, 2165; classed as saheeh by al-Albaani, 1758.
What this means is that the Shaytaan is present with them and provokes desire in each of them until he causes them to commit zina. End quote from Tuhfat al-Ahwadhi.
It was narrated from ‘Ali ibn Abi Taalib that a young woman from Khath’am came to the Prophet (peace and blessings of Allaah be upon him) and asked him a question. Al-Fadl ibn ‘Abbaas was riding behind him on the camel and he turned his face away. Al-‘Abbaas said: “O Messenger of Allaah, why did you turn away your cousin’s face?” He said: I saw a young man and a young woman and I did not feel sure that the Shaytaan would not try to influence them.”
Narrated by al-Tirmidhi (885); classed as saheeh by al-Albaani in Saheeh al-Tirmidhi. The hadeeth is also narrated in al-Saheehayn.
It says in Fataawa al-Lajnah al-Daa’imah (12/163):
Free mixing of men and women for education is haraam and is a great evil, because it involves fitnah, the spread of immorality and transgression of the sacred limits. The evil and moral corruption that has happened because of this mixing is the strongest evidence for it being haraam. End quote.
The Committee was also asked (17/66) the following question:
What is the Islamic ruling on friendships with the other sex, knowing that this friendship is decent and chaste and is known to all, with nothing hidden?
This is one of the most serious of haraam actions and the worst of evil deeds. It is not permissible for a woman to make friends with men who are not her mahrams, or vice versa, because that is a means that leads to fitnah and falling into evil deeds. End quote.
With regard to looking at her face, we have stated in the answer to question no. 1774 that deliberately looking at a non-mahram woman is haraam.
Our advice to you is to make a decision about this relationship. Either take her as your wife, if this girl is religiously-committed and of good character and you have grown fond of her, or cut off this relationship with her and close this door, for it is the door to evil and immorality, so do not leave it open lest you then regret it when regret will be to no avail.
And Allaah knows best.