MOUNT ARAFAT, Saudi Arabia — Some 2 million Muslims from around the world gathered Friday at a desert hill near Mecca in Saudi Arabia in an act of faith and repentance during the climactic emotional and spiritual moment of the annual hajj pilgrimage.

Men and women wept openly at Mount Arafat as they stretched their hands out in prayer and supplication, saying “Labayk, Allahuma, labayk,” – “Here I am, God, answering your call. Here I am.”

The faithful believe that on this day the gates of heaven are open, prayers are answered and past sins can be forgiven.

The pilgrimage is physically demanding and involves performing several rites, such as circling the cube-shaped Kaaba seven times at the start and finish of the hajj. It is a main pillar of Islam and one that all able-bodied Muslims must perform once in their lives.

Abdullahi Mu’azu K/Na’isa from Nigeria said he paid $5,000 to perform the hajj, and would do it again if he could. He said the day spent in Mount Arafat is his favorite moment of hajj because of its unity and diversity.

“Hajj brings happiness and oneness of all Muslims because you can see that all races are here, and it is a way to mingle with them and have a connection somewhere else,” he said.

All male pilgrims, regardless of wealth or status, wear seamless terry white cloths to symbolize equality before God during the hajj. Women cover their hair and wear long loose clothing, forgoing makeup and other adornments to help them detach from worldly pleasures and outward appearances.

The Prophet Muhammad is believed to have delivered his last sermon during the hajj at Mount Arafat 1,400 years ago.