Praise be to Allaah.
Allah, may He be exalted, in His wisdom has prescribed a variety of acts of worship for mankind in order to test them and show which among them are the best in deeds and most righteous. For people differ in their character and attitude. One of them may favour one type of worship because it suits him, but he may not favour another type because it does not suit him. So you will find that he does the former quickly and readily, but he does the latter slowly and reluctantly. The true believer is the one who submits to whatever will please his Lord, not what is in accordance with his whims and desires.
Among the varieties of worship are the various pillars of Islam. Some of them are purely physical, requiring effort and movement of the body, as in the case of prayer; some of them are physical but require refraining from things that are liked, as in the case of fasting; some of them are purely financial, as in the case of zakaah; and some of them are both physical and financial, as in the case of Hajj.
Hajj combines both physical and financial expenditure. Because it involves travel and more effort than other kinds of worship, Allah has only enjoined it once in a lifetime, and has stipulated that one must be able to do it. Being able to do it is a condition of an action being obligatory in this case and in others, but this condition of being able to do it is emphasized more in the case of Hajj more than in other cases. Hajj has great benefits, including the following:
1. It is undertaking one of the pillars of Islam without which it is not complete. This is indicative of its importance and shows that Allah loves it.
2. It is a kind of jihad for the sake of Allah; hence Allah mentions it after the verses of jihad. And it is proven in al-Saheeh that the Prophet (blessings and peace of Allah be upon him) said to ‘Aa’ishah (may Allah be pleased with her) when she asked him whether jihad is obligatory for women, “Yes, for them there is a jihad in which there is no fighting, Hajj and ‘Umrah.”
3. There is an immense reward for the one who does it in the prescribed manner. It is narrated in a saheeh report that the Prophet (blessings and peace of Allah be upon him) said: “An accepted pilgrimage brings no less a reward than Paradise.” And he said: “Whoever performs Hajj and does not commit any obscenity or commit any evil will go back (free of) sin as on the day his mother bore him”. And it was narrated that Abu Hurayrah (ra) said: The Messenger of Allah (blessings and peace of Allah be upon him) said: “The pilgrims performing Hajj and ‘Umrah are the guests of Allah; if they call upon Him He will answer them, and if they ask Him for forgiveness He will forgive them.” Narrated by al-Nasaa’i and Ibn Maajah.
4. In Hajj, remembrance of Allah is established, He is venerated and some rituals are carried out, such as reciting the Talbiyah, circumambulating the Ka‘bah (tawaaf), going between al-Safa and al-Marwah (saa‘i), standing in Arafat, staying overnight in Muzdalifah and stoning the Jamrah, along with what accompanies that of dhikr (remembrance of Allah), takbeer (proclaiming His greatness) and venerating Him. In the hadeeth it is narrated that the Prophet (blessings and peace of Allah be upon him) said: “Circumambulation of the Ka‘bah, going between al-Safa and al-Marwah and stoning the Jimaar have only been prescribed to establish the remembrance of Allah.”
5. During Hajj, Muslims from all parts of the world come together and show their love for one another and get to know one another. That is also accompanied by exhortations, guiding towards truth and encouraging people to adhere to it.
6. The Muslims demonstrate unity in time, place, actions and appearance. All of them stand in the different locations of Hajj at the same time, doing the same actions, wearing the same clothes (the izaar and rida’), with humbleness before Allah, may He be glorified and exalted.
7. The season of Hajj brings a great deal of good in both spiritual and worldly terms, as the Muslims may benefit by coming together, learning from one another and doing business. Hence Allah, may He be exalted, said (interpretation of the meaning): “That they may witness things that are of benefit to them” [al-Hajj . This includes both spiritual and worldly benefits.
8. It includes offering both obligatory and mustahabb sacrifices, which demonstrate respect for the rituals prescribed by Allah, and eating from the meat and giving some in charity to the poor.
The benefits and hidden wisdoms of Hajj are many.
( End quote from Majmoo‘ Fataawa Ibn ‘Uthaymeen, 24/239 )