Answer
Short Answer: No, not all prophets were direct blood descendants of Prophet Abraham. Lot, for example, lived during the same time period as Abraham, in a different land, and he came from the lineage of Prophet Noah. There are many prophets we are unaware of, but it’s very unlikely that someone like Buddha ever preached a monotheistic message that was somehow lost, as his focus was on living a simple, peaceful life, but without any direct relation to God.
Asalaamu alaykum and thank you for this question.
Why Did God Send Prophets?
To begin with, Allah, the Most Gracious, sent down prophets to mankind from time to time in order to serve as warners and guardians to the people.
Each messenger had a unique message of calling to the worship of Allah alone and averting the worship of false deities.
This tradition of sending prophets to their people arose after the innovation of ascribing partners with Allah.
Then Allah chose an anointed servant – a prophet among the people – in order to warn them of the evil consequences of their actions.
They called them to monotheism, which is the worship of the One true God.
And this is the purpose of our creation – to worship Allah.
And verily, We have sent among every Ummah (community, nation) a Messenger (proclaiming): Worship Allah (Alone) and avoid (or keep away from) Taaghoot (all false deities etc. do not worship Taaghoot besides Allah). Quran 16:36
Abraham: An Honored Prophet
Indeed Allah honored Ibrahim (Abraham) with prophethood and made it a successive tradition among his progeny.
He made him distinctive among the prophets and chose him above all mankind and jinn that existed during his time.
Indeed, Abraham was one prophet whose sons were prophets as well; he was the father of Ishmael and Isaac.
From the lineage of Ishmael arose the messenger – Muhammad (Peace Be Upon Him).
Isaac had a son, Jacob, who was a prophet. Among the sons of Jacob was Joseph, who was, as well, an apostle of God.
And a prophetic generation continued in that ancestral order.
So this may be the basis of your point with regards to all prophets being blood descendants of Abraham
However, we don’t find in the Qur’an, the sunnah, or in books of Islamic history any statement saying that all prophets were descendants of Abraham.
Prophet Lot, A Descendant of Noah, Not Abraham
Prophet Lot, for example, lived during the time of Prophet Abraham, but in a different land.
They both were sent on different missions to different people.
But how did we come to know this?
When Allah sent the angels to Abraham to give him glad tidings of a son, they equally mentioned that they have been sent to punish a people who had transgressed.
These were the people of Lot, according to the story found in Quran 15:51-70.
And the most likely genealogical tree of Lot took its root from Noah, who was also a messenger who came before Ibrahim.
So this tells us that not all prophets were blood descendants of Ibrahim.
However, all of mankind are descendants of Adam and many prophets were from the genealogy of Ibrahim.
God Sent Prophets Based On Need
So Allah sent prophets to people based on their location, their traditional practice, language, and so on.
Each prophet had a mission, an objective, and a set of people to reach out to.
For instance, Prophet Moses’ (Musa) mission was to debunk Pharaoh’s call to divinity and guide the children of Israel away from idolatry.
Aaron (Haroon), his brother, on the other hand, was just a supporter of the mission of Musa.
The majority of the prophets were sent to the children of Israel, owing to their transgression and willingness to oppose Allah’s injunctions.
It’s only Allah’s Apostle, Muhammad (Peace Be Upon Him) who has been sent to all of mankind and jinn.
Say [O Muhammad]: ‘O mankind! Verily, I am sent to you all as the Messenger of Allah.’ Quran 7:158
The universality of his message is sufficient as a proof for all of mankind.
The message of Islam has reached every nook and cranny of the world.
Regarding Buddha
As to your question on Buddha, the majority of the scholars do not ascribe prophethood to him, nor did Allah ordain him on a mission for tawhid.
History tells us that Siddhartha Gautama was his real name. He was said to be a prince and a monastic saint.
Gautama renounced his royal life and spent many years in meditation.
He sought a way for people to become liberated from their problems and attain lasting happiness.
As a result of his intense compassion for others and his deep understanding, he was able to overcome his shortcomings, limitations, and problems.
This was what led to a realization of his potential, and thus he became the Buddha.
On the contrary, Hamid Abdul Qadir in his book: “Buddha the Great: His life and Philosophy” postulates that Buddha was Dhu’l Kifl mentioned in the Qur’an.
However, the majority of the scholars identify Dhu’l Kifl with Ezekiel from the Hebrew scriptures.
This is to the best of our knowledge at this time.
Allah knows best and He is the Only One who is able to dispose of affairs.
Salam and please keep in touch.
(From Ask About Islam archives)
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