Was Sarah the biological sister or step-sister of Prophet Ibrahim according to Islamic sources?

According to authentic Islamic sources, Sarah was **not** the biological sister or step-sister of Prophet Ibrahim (Abraham, peace be upon him). She was his wife and his **sister in faith (Islam)**. The claim that she was his paternal half-sister originates from Judeo-Christian texts (Genesis 20:12) and Isra'iliyyat, not from authentic Islamic scripture. The authentic references on this matter are: 1. **Sahih al-Bukhari 3358 / Sahih Bukhari Hadees 3358** (and **Sahih Muslim 2371 / Sahih Muslim Hadees 2371**): When Prophet Ibrahim (A.S.) entered the land of a tyrant ruler with Sarah, he referred to her as his sister to protect them from harm. He then explicitly clarified the meaning of this statement to Sarah, saying: *"There are no believers on the face of the earth besides you and me. Verily, you are my sister in faith, so do not contradict my statement."* 2. *Is baat ka koi authentic scriptural reference Quran ya Sahih Hadees mein nahi milta* that Sarah was Prophet Ibrahim's biological step-sister. In Islam, marriage to one's sister (including a half-sister or step-sister sharing a parent) is strictly prohibited (Surah An-Nisa 4:23 / Surah An-Nisa Ayat 23).