On the authority of Abu 
Hurairah – may Allâh be pleased with him – who said, "'Indeed a youth 
came to the Prophet – Sallallâhu alayhi wa sallam –  and said, 'O 
Messenger of Allâh, permit me to fornicate.'" When he said that, those 
present turned at him and rebuked him; they said, 'Stop that!' 
              The Prophet  – Sallallâhu alayhi wa sallam –  said, 'Come over.'
               Worse than stealing, fornication and taking of intoxicants!
              
                  
                The lad went nearer to the Messenger of Allâh  – 
Sallallâhu alayhi wa sallam –  and the latter asked the former to sit.
                
                
                  
                The Messenger of Allâh  – Sallallâhu alayhi wa sallam –  said, 'Do you like it for your mother?'
                
                
                The lad replied, 'No; by Allâh, make Allâh make me your ransom.'
                
                
                Then the Messenger of Allâh  – Sallallâhu alayhi wa 
sallam –  said, 'People too will not like it for their mothers.'
                
                
                He  – Sallallâhu alayhi wa sallam –  said further, 'Do you like it for your daughter?'
                
                
                The lad replied, 'No; by Allâh, make Allâh make me your ransom.'
                
                
                Then the Messenger of Allâh  – Sallallâhu alayhi wa 
sallam –  said, 'People too will not like it for their daughters.'
                
                
                He  – Sallallâhu alayhi wa sallam –  said, 'Do you like it for your sister?'
                
                
                The lad replied, 'No; by Allâh, make Allâh make me your ransom.'
                
                
                Then the Messenger of Allâh  – Sallallâhu alayhi wa 
sallam –  said, 'People too will not like it for their sisters.'
                
                
                He  – Sallallâhu alayhi wa sallam –  said, 'Do you like it for your paternal aunt?'
                
                
                The lad replied, 'No; by Allâh, make Allâh make me your ransom.'
                
                
                Then the Messenger of Allâh  – Sallallâhu alayhi wa 
sallam –  said, 'People too will not like it for their paternal aunts.'
                
                
                He  – Sallallâhu alayhi wa sallam –  said, 'Do you like it for your maternal aunts?'
                
                
                The lad replied, 'No; by Allâh, make Allâh make me your ransom.'
                
                
                Then the Messenger of Allâh  – Sallallâhu alayhi wa 
sallam –  said, 'People too will not like it for their maternal aunts.'
                
                
                After all that, the Messenger of Allâh  – Sallallâhu 
alayhi wa sallam –  put his hand on him and said: 'O Allâh, forgive him,
 cleanse his heart and make his private-part chaste.' Thereafter, the 
lad refrained from looking at anything.
                
			
			
               [Al-Imâm Ahmad (21676).] 
            
On the authority of Imrân bn Husayn – may Allâh be pleased with him –, the Prophet  – Sallallâhu alayhi wa sallam –  said: 
'When you see an adulterer, thief, and drunkard what will you say about them?' 
They replied:
'Allâh and His Messenger know better.' 
He  – Sallallâhu alayhi wa sallam –  said: 
'They are detestable acts and there are punishments for them. But won't I
 inform you of the most heinous sins? It is associating partners with 
Allâh; Allâh the Mighty said: 
'…and whoever sets up partners with Allâh in worship, he has indeed 
invented a tremendous sin;' so also is disobeying the parents,' then he 
said, 'Give thanks to Me and to your parents, unto me is the final 
destination.' 
The reporter – may Allâh be pleased with him – said: 
"'He  – Sallallâhu alayhi wa sallam –  was reclining then he sat upright and said:
'So also is false speech! So also is false speech!'"
[Ibn Hajar Al-Asqalâni – may Allâh bestow mercy on him – recorded it in Al-Mattâlib Al-Aaliyah,
 Book of Faith and Oneness of Allâh, Chapter of Explanation of Major 
Sins (number: 3004). Ibn Hajar – may Allâh bestow mercy on him – also 
recorded its like in Muwâfaqatul-Khabar Al-Khabar (vol.1/356) and he 
said it is hasan gharîb as reported via Al-Hasan (bn al-Basrî) – may 
Allâh bestow mercy on him –, and Azîz (another form of strong chain) as 
reported via Qatâdah. Mâlik also recorded the like of the hadith in 
Al-Muwata'a, Book of Shortening the Prayers on Journeys, the Chapter of 
Action in Whole Prayer (number: 409).]

