One day Ibn Umar (Radiallahu Ta’ala Anhu) was sitting with the Prophet (Sal Allaahu Alaiyhi wa Sallam) in the masjid in Mina when a man from the Ansaar and a man from the Thaqeef came. They gave Salaam and said, "O Messenger of Allaah, we came to ask you questions."
So the Messenger (Sal Allaahu Alaiyhi wa Sallam) said: "If you want I can inform you why you came and what you want to ask, and I will do so, and if you want I will hold back and you can ask me and I will answer you."
They said: "Tell us O Messenger of Allaah!"
The man from Thaqeef said to the Ansaari: "Ask." So the Ansaari man said: "Inform me O Messenger of Allaah!"
The Messenger of Allaah (Sal Allaahu Alaiyhi wa Sallam) said: "You came to me, to ask about leaving your house and aiming for the Bait-ul-Haraam and the reward for it; about praying two Rakah after Tawaaf and the reward for it; going between as-Safa and Marwa and the reward for it; your staying the evening in Mina, and the reward for it; stoning the Jamarah and the reward for it; slaughtering an animal and the reward for it; and the Tawaaf of al-Ifaadh."
The man said: "I swear by the One who sent you with the truth! This is what I came to ask you about."
The Prophet (Sal Allaahu Alaiyhi wa Sallam) said: "As for you leaving your homes aiming for the Bait-ul-Haraam: then your she-camel does not place its foot nor does it raise it except that Allaah writes for you a reward due to it, and wipes off one of your sins.As for the two Rakah after the Tawaaf, then it is equivalent to freeing a slave from the Children of Ismaeel.
As for your circuiting of as-Safa and al-Marwa, then it is the same as freeing 70 slaves.
As for you staying till the evening in Arafah, then Allaah descends to the sky of the Duniya and He boasts about you to the Angels, and says: 'My slaves have come to Me, looking rough, from every deep valley hoping for My mercy, so if their sins were equivalent to the amount of sand or the drops of rain or like the foam on the sea I will forgive them. So go forth My slaves! Having forgiveness and for what or who you have interceded for.'
As for stoning the Jamaar (the pillars), then for every stone that you throw, it removes a big sin from the deadly sins.
As for your slaughtering, then it is saved for you with your Lord.
As for shaving your head, then there is a reward for every strand of hair that you shaved, and a sin is wiped off by it.
As for you performing Tawaaf of the House after all this, then by this time you are performing Tawaaf with no sin upon you and an Angel comes and places his hand between your shoulders saying: "Perform good deeds in what you face of the future, for verily your past sins have been forgiven."
(at-Tabarani and al-Bazaar--graded hasan by Al-Albaanee in Saheeh al-Targheeb wa Tarheeb')