Allah (Glorified and Exalted be He) has made it obligatory on His Slaves to perform pilgrimage to His Sacred House, making it one of the pillars of Islam. Allah (Exalted be He) says:
And Hajj (pilgrimage to Makkah) to the House (Ka‘bah ) is a duty that mankind owes to Allâh, for those who are able to undertake the journey; and whoever disbelieves [i.e. denies Hajj (pilgrimage to Makkah), then he is a disbeliever of Allâh], then Allâh stands not in need of any of the ‘Alamîn (mankind, jinn and all that exists)
It is also reported in the Two Sahih (authentic) Books of Hadith (i.e. Al-Bukhari and Muslim) from Ibn `Umar (may Allah be pleased with him and his father) that the Prophet SallAllaahu alayhi wa sallam (peace be upon him) said: “Islam is based on five pillars: Testimony testify that there is none worthy of worship (in truth) but Allah and that Muhammad is the Messenger of Allaht and that Muhammad is the Messenger of Allah; performing Salah (prayers), giving Zakah; observing Sawm (Fast) in Ramadan; and performing Hajj (pilgrimage) to the Sacred House of Allah.”
Thus, it is obligatory on those who did not perform Hajj in spite of their being able to do it to hasten to perform it, as it is reported from Ibn `Abbas (may Allah be pleased with him) that the Prophet SallAllaahu alayhi wa sallam (peace be upon him) said: “Hasten to perform your (obligatory) Hajj, for one does not know what will happen to him (that could prevent him from performing it).” (Related by Ahmad)
Moreover, performing Hajj is obligatory for those who can afford the expenses for the journey. This is grounded on the literal meaning of Allah’s (Exalted be He) saying: (And Hajj (pilgrimage to Makkah) to the House (Ka‘bah ) is a duty that mankind owes to Allâh, for those who are able to undertake the journey; and whoever disbelieves [i.e. denies Hajj (pilgrimage to Makkah), then he is a disbeliever of Allâh], then Allâh stands not in need of any of the ‘Alamîn (mankind, jinn and all that exists).
And on the Prophet’s SallAllaahu alayhi wa sallam (peace be upon him) saying in his sermon: (O people, Allah has made Hajj obligatory upon you, so perform it). (Reported by Muslim)
Another Hadith is that related from `Aishah (may Allah be pleased with her) that she said: (O Messenger of Allah, are women obliged to perform Jihad? He said: Indeed, they have to perform a (kind of) Jihad that involves no fight; Hajj and `Umrah.) (Related by Ahmad and Ibn Majah through an authentic chain of narration)
On the other hand, Hajj and `Umrah are obligatory only once in a lifetime, as it was authentically reported that the Prophet SallAllaahu alayhi wa sallam (peace be upon him) said: (Hajj is (obligatory only) once, so whoever performs it more than that, it would be (regarded as) a supererogatory act.)
Moreover, it is recommended to perform Hajj and `Umrah frequently as a supererogatory act of worship, since it was authentically related in the Two Sahih Books of Hadith from Abu Hurayrah (may Allah be pleased with him) that the Prophet SallAllaahu alayhi wa sallam (peace be upon him) said: (The performance of) `Umra is an expiation for the sins committed (between it and the previous one). And the reward of Hajj Mabrur (the one accepted by Allah) is nothing except Paradise.
When a Muslim intends to travel to perform Hajj or `Umrah, it is recommended that they advise their family and friends to adhere to Taqwa (fear/wariness of offending Allah), which means complying with Allah’s (Glorified and Exalted be He) Commands and avoiding His Prohibitions.
The real essence of repentance is to abandon and keep away from sins, regret previously-committed sins, and determine not to return to them again. Furthermore, if such sins involve doing wrong to people, through killing, stealing, or slandering, people should return what they had seized unjustly or seek the forgiveness of those whom one had wronged before traveling. Prophet (peace be upon him) said: (He who has done wrong to his fellow (Muslim), through calumniation or seizure of his property, let him ask his forgiveness today before the time (i.e. the Day of Resurrection) when there will be neither dinar nor dirham. If he has done some good deeds, a portion equal to his wrong doings will be subtracted from them; but if he has no good deeds, he will be burdened with the evil deeds of the one he had wronged in the same proportion.)
They should also choose from their wealth, for the expenditure of Hajj and `Umrah, money which is purely and lawfully obtained, since it was authentically reported from the Prophet (peace be upon him) that he said: (Allah (Exalted be He) is Good and does not accept anything but that which is good.) . Moreover, Al-Tabarany related from Abu Hurayrah (may Allah be pleased with him) that the Prophet (peace be upon him) said:
(When a pilgrim sets out for Hajj with lawful and pure earnings, and he says: “Labbayka Allahumma labayk”, a caller calls him from Heaven saying: “Labbayka wa Sa`dayka (You will be given continuous help in carrying out your acts of worship). Your provision is lawful and your mount (means of transportation) is lawful”. But, if he sets out with unlawful means and says, “labbayka”, a caller from Heaven will call him saying: “Laa labbayka walaa Sa`dayk (Your Talbiyah is not accepted and there is no help for you in carrying out your worship)”, for your provision is from unlawful means and your earnings are from unlawful means and your Hajj is not accepted.)