Prophet’s verdict was regarded as judged by Quran
 And from the same chain of narration from Ubaydullah Ibn Abdullah Ibn Utba Ibn Mas’ud that Abu Hurayra and Zayd Ibn Khalid al-Juhani (Radi Allahu Anhuma) informed him that two men brought a dispute to the Messenger of Allah (Sallalahu Alayhi Was-Sallam). One of them said, “Messenger of Allah! Judge between us by the Book of Allah!” The other said, and he was the wiser of the two, “Yes, Messenger of Allah. Judge between us by the Book of Allah and give me permission to speak.” He said, “Speak.” He said, “My son was hired by this person as a labourer (worker, workman) and he committed fornication with his wife. He told me that my son deserved stoning, and I ransomed him for one hundred sheep and a slave-girl. Then I asked the people of knowledge and they told me that my son deserved to be flogged with one hundred lashes and exiled for a year, and they informed me that the woman deserved to be stoned.” The Messenger of Allah (Sallalahu Alayhi Was-Sallam) said, “By him in whose Hand my life is, I will judge between you both by the Book of Allah. As for your sheep and slave girl, they should be returned to you. Your son should have one hundred lashes and be exiled for a year.” He ordered Unays al-Aslami to go to the wife of the other man and to stone her if she confessed. She confessed and he stoned her.
Imam Malik said, “A labourer (workman) is called an Asif”
Hafidh zubair `ali zai rahimahullah mentioned a very important benefit :
Stoning is not mentioned clearly in the Quran, however it is known from the saying of the Prophet (Sallalahu Alayhi Was-Sallam), “I will judge between you both by the Book of Allah (Quran).” that the hadith is also the Book of Allah (Quran) therefore the rejector of stoning is a rejector of the Book of Allah (Quran).
The decision and judgment for all the differences should be in accordance to the hadith of the Messenger of Allah (Sallalahu Alayhi Was-Sallam). Imam Sufyan Ibn Uyayna Maki used to say, “Without a shadow of a doubt the Messenger of Allah (Sallalahu Alayhi Was-Sallam) is the greatest balance (weigh scale). So everything will be referred back to him. In accordance to his manners, his lifestyle, and his way. So whatever is in accordance to him then that will be the truth and whatever goes against him then that will be false.” (al-Jami’ ul-Akhlaq ar-Rawi Wa Adab us-Sami’ of al-Khatib (1/79) hadith (no.8) and its chain is [Hasan] good)
Hadeeth rejectors who deny stoning should see this link: http://icraa.org/opposition-to-rajm-stoning-analysis-and-refutation/