Narrated 'Abdullah:
"I said: 'O Messenger of Allah (ﷺ)! What is the worst sin?' He said: 'That you make and equal to Allah, while it is He who created you.'" He said: "I said: 'Then what?' He said: 'That you kill your child fearing that he will eat with you.'" He said: "I said: 'Then what?' He said: 'That you commit adultery with your neighbors wife.'" (ES)
English reference (ES): Vol. 5, Book 44, Hadith 3182 (ES)
Arabic reference (ES): Book 47, Hadith 3482 (ES)