Volume 4, Book 52, Number 250 :
Narrated by Ibn Abbas (radiallaahu `anhu)
That he heard the Prophet (sallallaahu `alayhi wasallam) saying, “It is not permissible for a man to be alone with a woman, and no lady should travel except with a Mahram (i.e. her husband or a person whom she cannot marry in any case for ever; e.g. her father, brother, etc.).” Then a man got up and said, “O Allah’s Apostle! I have enlisted in the army for such-and-such Ghazwa and my wife is proceeding for Hajj.” Allah’s Apostle (sallallaahu `alayhi wasallam) said, “Go, and perform the Hajj with your wife.”
It is not permissible for a man to be alone with a woman who is not his mahram, because the Prophet (blessings and peace of Allah be upon him) said: “No man should be alone with a woman unless there is a mahram with them.” Narrated by al-Bukhaari (1862) and Muslim (1341). And he (blessings and peace of Allah be upon him) said: “No man is alone with a woman but the Shaytaan is the third one present.” Narrated by al-Tirmidhi (1171) and classed as saheeh by al-Albaani in Saheeh al-Tirmidhi.
Al-Nawawi (may Allah have mercy on him) narrated in Sharh Muslim (14/153) that there was consensus among the scholars that it is haraam for a man to be alone with a woman who is not his mahram. This was narrated by al-Haafiz in al-Fath (4/77).
“Being alone with” (khalwah) refers to when the man and woman are in a place where no one can see them.
The scholars of the Standing Committee for Issuing Fatwas were asked: Does khalwah (“being alone with”) refer to when a man is alone with a woman in some house, far away from the eyes of people, or does it refer to any situation in which a man is alone with a woman, even if they can be seen by others?
They replied: What is meant by the “being alone with” (khalwah) that is forbidden in sharee‘ah is not only when a man is alone with a woman who is not his mahram in a place where they cannot be seen; rather it also includes situations in which he is alone with her in a place where she can converse with him and he can converse with her, even if they can be seen by other people, but their words cannot be heard, whether that is out in the open or in a car or on the roof of a house, and so on. That is because khalwah has been forbidden because it is the harbinger of zina and the means that leads to it. So everything that could lead to that, even making an arrangement to do that later, comes under the ruling of physical khalwah or being alone in a place where they cannot be seen. End quote.
Shaykh ‘Abd al-‘Azeez ibn ‘Abd-Allah ibn Baaz; Shaykh ‘Abd al-Razzaaq ‘Afeefi; Shaykh ‘Abd-Allah ibn Ghadyaan; Shaykh ‘Abd-Allah ibn Qa ‘ood
Fataawa al-Lajnah al-Daa’imah, 17/57
Khalwah can be avoided with the presence of a mahram or the presence of a righteous woman, according to the correct opinion.
It says in Asna’l-Mataalib (3/407): It is permissible for a man to be alone with two women, but not the opposite; i.e., it is not permissible for two non-mahram men to be alone with a woman even if it is unlikely that they would agree to commit immoral actions, as was clearly stated by al-Nawawi in al-Majmoo‘; that is because a woman feels more shy of another woman than a man feels shy of another man.
Hadith no. 2636 (below) is a repeat. Read it here.
Volume 4, Book 52, Number 240 :
Narrated by Jabir bin ‘Abdullah (radiallaahu `anhu)
On the day of the battle of the Trench, the Prophet (sallallaahu `alayhi wasallam) wanted somebody from amongst the people to volunteer to be a reconnoiter. Az-Zubair (radiallaahu `anhu) volunteered. He demanded the same again and Az-Zubair (radiallaahu `anhu) volunteered again. Then he repeated the same demand (thrice) and Az-Zubair (radiallaahu `anhu) volunteered once more. The Prophet (sallallaahu `alayhi wasallam) then said, ” Every prophet has a disciple and my disciple is Az-Zubair.”
Volume 4, Book 52, Number 241 :
Narrated by Ibn’ Umar (radiallaahu `anhu)
From the Prophet (sallallaahu `alayhi wasallam) the following Hadith (No. 242).
Volume 4, Book 52, Number 242 :
Narrated by Ibn ‘Umar (radiallaahu `anhu)
The Prophet (sallallaahu `alayhi wasallam) said, “If the people knew what I know about traveling alone, then nobody would travel alone at night.”
Imam Ahmad was asked about a man spending the night alone. He said: I prefer him to avoid that. Quoted from al-Adaab al-Shar’iyyah (1/428).
It was narrated from ‘Abd-Allaah ibn ‘Amr ibn al-‘Aas that the Prophet (peace and blessings of Allaah be upon him) said: “The (lone) rider is a devil, two riders are two devils and three are a travelling party.” Narrated by al-Tirmidhi (1674), who said it is a hasan hadeeth. It was also classed as hasan by Ibn Hajar in Fath al-Baari (6/53) and by al-Albaani in al-Silsilah al-Saheehah (62).
These ahaadeeth indicate that it is makrooh to be alone in situations where a man fears for himself because of weakness, severe exhaustion or hardship, or when he fears that the shaytaan may tempt him and mislead him. The benefit of being with righteous companions is not limited to help and support, rather the most important thing is that it helps him to remain steadfast and pious, for the shaytaan is further away from two.
Al-Haafiz Ibn Hajar said in Fath al-Baari (6/53):
Ibn Khuzaymah reported it under the heading; “the prohibition on two travelling and that less than three are sinners,” because what is meant by “devil” is a sinner. Al-Tabari said: This is a rebuke aimed at disciplining and guiding because of the fear of loneliness for one, but it is not haraam. The one who travels alone in the wilderness and the one who stays alone in a house has no guarantee that he will not feel lonely, especially if he had bad thoughts and is weak in faith.
In fact people differ with regard to that and the prohibition concerning that is a measure of protection, but if there is need for that, it should be fine. It was said, commenting on the words “the (lone) rider is a devil” that his travelling alone is suggested to him by the shaytaan, or he is likened to the shaytaan in his actions. And it was said that it is disliked because if the person who is travelling alone dies on the journey, there will be no one who can take care of him; similarly, if two are travelling and both or one die, there will be no one to help, unlike three, because in most cases that fear will not be present. End quote.
The apparent meaning of the hadeeth is that the prohibition applies to the one who travels alone via empty and remote routes. As for well-travelled routes, and those in which there is no risk of being lost, and where there are likely to be helpers and companions, there is no report that it is makrooh or prohibited. The same applies to travelling nowadays on planes, ships and buses, because those who are in them are all regarded as traveling companions, so the one who travels by these means is not alone in the sense that is forbidden.
Shaykh Ibn ‘Uthaymeen said in Fataawa Noor ‘ala al-Darb (mutafarraqaat/al-adaab):
This points to the warning against travelling alone, but that applies to journeys where the route is not travelled by many. As for journeys where the route is travelled by many, and it is as if one is in the middle of a village, such as the route from al-Qaseem to Riyadh, or Riyadh to Dammam and other such routes where there are many travellers, and the road to the Hijaz during the Hajj season, this is not in fact regarded as being alone, because many people travel by these routes. So a person may be alone in his car but he is not alone on the journey, rather there are people around him, behind him and in front of him at every moment. End quote.
Shaykh al-Albaani said in his commentary on this hadeeth in al-Saheehah (62):
Perhaps the hadeeth refers to travelling in the deserts or wilderness where the traveller rarely sees anyone. It does not include travel nowadays on paved and well-travelled roads. And Allaah knows best. End quote.
Taken from IslamQA
Volume 4, Book 52, Number 243 :
Narrated by Hisham’s father
Usama bin Zaid (radiallaahu `anhu) was asked at what pace the Prophet (sallallaahu `alayhi wasallam) rode during Hajjat-ul-Wada’ “He rode at a medium pace, but when he came upon an open way he would go at full pace.”
Volume 4, Book 52, Number 244 :
Narrated by Aslam
While I was in the company of ‘Abdullah bin ‘Umar (radiallaahu `anhu) on the way to Mecca, he received the news of the severe illness of Safiya bint Abi Ubaid (i.e. his wife), so he proceeded at greater speed, and when the twilight disappeared, he dismounted and offered the Maghrib and ‘Isha ‘prayers together and said, “I saw the Prophet (sallallaahu `alayhi wasallam) delaying the Maghrib prayer to offer it along with the ‘Isha’ when he was in a hurry on a journey.”
Volume 4, Book 52, Number 245 :
Narrated by Abu Huraira (radiallaahu `anhu)
Allah’s Apostle (sallallaahu `alayhi wasallam) said, “Journey is a piece of torture, for it disturbs one’s sleep, eating and drinking. So, when you fulfill your job, you should hurry up to your family.”
When they make fun of you, laugh at your face
When following Allah’s commands is taken as a disgrace
When you feel like a stranger amidst a friendly crowd
When your heart aches to be away from what’s about
When for once, you want to put down the pretense
And tell them what you think, even if they take offence
When you know you have to be quiet only for Allah’s sake
Though you feel you just can’t bear it, you’re just ready to break
Then know you’re on the path that the Prophets tread on
The best people of this earth, they were Allah’s beloved ones
Think of Ibrahim, threatened by his own kin
Thrown into the fire, with no guilt or sin
Think of Nuh, carrying God’s Word for 950 years
Steadily carving his ship of refuge amid all the jeers
Think of Hud, scorned and rejected, openly by his own nation
Yet he placed his trust in He, Who has in His Hands forelocks of all creation
Think of Saalih, patiently showing proofs to clear every doubt
But they slaughtered the she-camel without shame of any amount
Think of Lut, stopping his people from committing the most heinous sin ever
He felt in need of support, it was more than he could endeavor
Think of Shu`aib, trying his best to teach people to be just
Telling them to place in only Allah their trust
Think of Musa, inviting the Pharaoh to Oneness of God
Pharaoh who himself claimed to be the greatest lord
Think of Yusuf, a lone child down the well
Later sent to jail, though no blame on him befell
Think of Muhammad, who endured more hardships than any other being
Abused, mocked, hurt, accused, still never thought of fleeing
So if among the people, you feel shivers and go cold
Loneliness overcomes you, you can’t take anymore
Remember you’re a stranger on this perishable land
Meant to go back to Him, Who is always close at hand
May Allah’s peace and blessings be upon all His Prophets. Ameen.
Narrated Ibn ‘Umar:
The Prophet said, “A woman should not travel for more than three days except with a Dhi-Mahram (i.e. a male with whom she cannot marry at all, e.g. her brother, father, grandfather, etc.) or her own husband.)”
The Prophet said, “A woman should not travel for more than three days except with a Mahram.”
Narrated Abu Huraira:
The Prophet (p.b.u.h) said, “It is not permissible for a woman who believes in Allah and the Last Day to travel for one day and night except with a Mahram.”
The saheeh (authentic) Sunnah indicates that it is not permissible for a woman to travel except with a mahram. This travelling is not defined by a specific distance, as is the case with shortening the prayers or breaking the fast, rather everything that is called travelling, whether it is long or short, is not permitted for a woman unless she has a mahram with her.
Al-Bukhaari (1729) and Muslim (2391) narrated that Ibn ‘Abbaas (may Allaah be pleased with him) said: The Prophet (peace and blessings of Allaah be upon him) said: “No woman should travel except with a mahram.”
The fuqaha’ are unanimously agreed that it is haraam for a woman to travel without a mahram, except in a few exceptional cases, such as travelling for the obligatory Hajj, for which some of them have permitted a women to travel with trustworthy companions. Al-Haafiz Ibn Hajar (may Allaah have mercy on him) said: al-Baghawi said: They did not differ concerning the fact that a woman may not travel for anything but the obligatory Hajj except with a husband or mahram, except a kaafir woman who becomes Muslim in daar al-harb or a female captive who escapes. Others added: or a woman who becomes separated from her group and is found by a trustworthy man, in which case it is permissible for him to accompany her until he brings her back to her group. End quote from Fath al-Baari (4/76).
For a very detailed and satisfactory answer, including the wisdom and reasons behind this ruling, read this.