Khalid moves to Najd against the rebel tribe of Banu Tamim and their Sheikh Malik ibn Nuwayrah.

At Najd, getting the news of Khalid's decisive victories against apostates in Buzakha, many clans of Banu Tamim hasten to visit Khalid, but the Banu Yarbu', a branch of Bani Tamim, under their chief, Malik ibn Nuwayrah, hangs back.

Malik is a chief of some distinction: a warrior, noted for his generosity, and a famous poet.

At the time of Muhammad, he had been appointed as a tax collector for the tribe of Banu Tamim.

As soon as Malik heard of the death of Muhammad, he gave back all the tax to his tribespeople, saying, "Now you are the owner of your wealth."

His riders are stopped by Khalid's army at the town of Buttah.

Khalid asks them about the signing of pact with Sajjah; they said it was just because they wanted revenge against their terrible enemies.

When Khalid reaches Najd he finds no opposing army.

He sends his cavalry to nearby villages and orders them to call the Azaan (call for prayers) to each party they meet.

Zirrar bin Azwar, a squadron leader, arrests the family of Malik, claiming they had not answered the call to prayer.

Malik avoids direct contact with Khalid's army and orders his followers to scatter, and he and his family apparently move away across the desert.

He refuses to give zakat, hence differentiating between prayer and zakat.

Nevertheless, Malik is accused of rebellion against the state of Medina.

He is also to be charged for his entering in an anti-Caliphate alliance with Sajjah, a self-proclaimed prophetess.

Malik is arrested along with his clansmen, and is asked by Khalid about his crimes.

Malik's response is "your master said this your master said that" referring to Abu Bakr.

Khalid declares Malik a rebel apostate and orders his execution.

Khalid bin Walid kills Malik ibn Nuwayra.

In Medina, ‘Umar told Khâlid: “You enemy of Allâh!

You killed a Muslim man and then rape his wife.

By Allâh, I will stone you".

Khalid had taken Malik’s wife, Layla bint al-Minhal.

Shias claim that Islamically, Khalid would have had to wait for her to complete the waiting period iddah (three menstrual cycles) before Khalid would have been able to marry her.

Sunnis believe that since Malik and his tribe were judged apostates, they were taken captives and Idda rules do not apply to apostates.

Shias also claim that Abu Qatada Ansari was so shocked at Malik's murder by Khalid that he immediately returned to Medina, and told Abu Bakr that he would not serve under a commander who had killed a Muslim.

The death of Malik and Khalid's taking of his wife Layla creates a controversy.

Some officers of his army—including a prominent companion of Muhammad, Abu Qatadah—believe that Khalid killed Malik to take his wife.

After the pressure exerted by Umar—Khalid's cousin and one of Caliph Abu Bakr's main advisors—Abu Bakr calls Khalid back to Medina to explain himself.