Allah the Most High Says in Surah Al-Hajj, Verse 26-28
وَإِذْ بَوَّأْنَا لِإِبْرَاهِيمَ مَكَانَ الْبَيْتِ أَن لَّا تُشْرِكْ بِي شَيْئًا وَطَهِّرْ بَيْتِيَ لِلطَّائِفِينَ وَالْقَائِمِينَ وَالرُّكَّعِ السُّجُودِ
And (remember) when We showed Ibrahim (Abraham) the site of the (Sacred) House (the Ka’bah at Makkah) (saying): “Associate not anything (in worship) with Me, [La ilaha ill-Allah (none has the right to be worshipped but Allah Islamic Monotheism], and sanctify My House for those who circumambulate it, and those who stand up for prayer, and those who bow (submit themselves with humility and obedience to Allah), and make prostration (in prayer, etc.);”
وَأَذِّن فِي النَّاسِ بِالْحَجِّ يَأْتُوكَ رِجَالًا وَعَلَىٰ كُلِّ ضَامِرٍ يَأْتِينَ مِن كُلِّ فَجٍّ عَمِيقٍ
And proclaim to mankind the Hajj (pilgrimage). They will come to you on foot and on every lean camel, they will come from every deep and distant (wide) mountain highway (to perform Hajj).
لِّيَشْهَدُوا مَنَافِعَ لَهُمْ وَيَذْكُرُوا اسْمَ اللَّهِ فِي أَيَّامٍ مَّعْلُومَاتٍ عَلَىٰ مَا رَزَقَهُم مِّن بَهِيمَةِ الْأَنْعَامِ فَكُلُوا مِنْهَا وَأَطْعِمُوا الْبَائِسَ الْفَقِيرَ
That they may witness things that are of benefit to them (i.e. reward of Hajj in the Hereafter, and also some worldly gain from trade, etc.), and mention the Name of Allah on appointed days (i.e. 10th, 11th, 12th, and 13th day of Dhul-Hijjah), over the beast of cattle that He has provided for them (for sacrifice) (at the time of their slaughtering by saying: Bismillah, WAllahu-Akbar, Allahumma Minka wa Ilaik). Then eat thereof and feed therewith the poor who have a very hard time.