Whoever tells that Muhammad concealed part of what was revealed to him, is a liar, for Allah says:-- "O Apostle (Muhammad)! Proclaim (the Message) which has been sent down to you from your Lord." (5.67)
Sahih al-Bukhari Book 65, Hadith 134
← Previous Hadith Ar-Rubai (the paternal aunt of Anas bin Malik) broke the incisor tooth of young Ansari girl. Her family demanded the Qisas and they came to the Prophet (ﷺ) who passed the judgment of Qisas. Anas bin An-Nadr (the paternal uncle of Anas bin Malik) said, "O Allah's Messenger (ﷺ)! By Allah, her tooth will not be broken." The Prophet (ﷺ) said, "O Anas! (The law prescribed in) Allah's Book is Qisas." But the people (i.e. the relatives of the girl) gave up their claim and accepted a compensation. On that Allah's Apostle said, "Some of Allah's worshippers are such that if they take an oath, Allah will fulfill it for them."

Sahih al-Bukhari Book 65, Hadith 133 Next Hadith → This Verse: "Allah will not punish you for what is unintentional in your oaths." (5.89) was revealed about a man's state men (during his talk), "No, by Allah," and "Yes, by Allah."

Sahih al-Bukhari Book 65, Hadith 135