The splitting of the moon

When the Holy Prophet (Sallallahu alaihi wa sallam) started inviting the whole of humanity towards Islam and started granting them the belief in the unity of Allah Ta'ala and His own Prophethood, the Makkans wanted to stop His Da'wah activities. 

Thus, Abu Jahl called one of his friends Habeeb Yemeni to Makkah to stop the people of Makkah from embracing Islam.  When Habeeb Yemeni reached Makkah, Abu Jahl started complaining about the Holy Prophet (Sallallahu alaihi wa sallam).  On listening to all of this, Habeeb Yemeni said that first he will meet Him. 

He sent a messenger to the Holy Prophet (Sallallahu alaihi wa sallam) that Habeeb Yemeni along with the elite of Makkah wants to meet at such and such a place.  The Holy Prophet (Sallallahu alaihi wa sallam) went there.  It was a full moon night.   

Habeeb Yemeni asked the Holy Prophet (Sallallahu alaihi wa sallam): 

What do you invite people to? 

The Holy Prophet (Sallallahu alaihi wa sallam): 

That Allah is One and only and that I am the Prophet of Allah Ta'ala. 

Habeeb Yemeni: 

If you are Prophet, then what is your miracle as a sign of Prophethood? 

The Holy Prophet (Sallallahu alaihi wa sallam): 

I am ready to show you whatever miracle you desire. 

Habeeb Yemeni:

 I want to see 2 miracles.  One, that you split the moon and the second that you yourself tell me what I want. 

The Holy Prophet (Sallallahu alaihi wa sallam) along with all the chiefs of Quraish, went to the mountain of Safa.  He (Sallallahu alaihi wa sallam) gestured at the moon with His blessed finger and immediately the moon split into 2 and everybody saw it with their own eyes.  Then again the Holy Prophet (Sallallahu alaihi wa sallam) gestured and the 2 parts of the moon rejoined. 

After this, the Holy Prophet (Sallallahu alaihi wa sallam), for whom Allah Ta'ala has made plain what lies in the hearts, told Habeeb Yemeni: 

O Habeeb Yemeni!  You have a daughter, who is blind, deaf and lame.  You desire that she get cured.  Go!  Your daughter is cured. 

He only had to listen to this, that Habeeb Yemeni recited the Kalima Shahadah and entered the fold of Islam.

 When he went to his house, he saw that the girl who was handicapped earlier is herself opening the door.  He asked her:  Daughter!  What happened?  She said:  Father!  I saw a dream that a very beautiful and radiant person came to me, made me a Muslim by reciting the Kalima Shahadah and passed His hand over my body and I was cured that very moment.  ('Aseedatush Shahadah Sharh Qaseedatul Burdah, Imam Umar Bin Ahmad Kharbooti, Pg. No. 122)