Mursal hadeeth(A Tabiyee narrating directly from Prophet peace be upon him leaving a sahabi from the chain), Mursal hadeeth is not evidence according to the Majority of the scholars of Islam, Including Companions of Prophet peace be upon him, and the claim that Imam Ash Shafiee was the first one who rejected mursal is false claim, Proof for this claim is are as follows :-
IT IS MENTIONED IN MUQADDIMAH OF SAHIH MUSLIM MUJAHID SAID :-
Basheer bin Ka’ab (Tabiyee) came to Ibne Abbas (Sahabi) and said Prophet peace be upon him said this(he again said) Prophet peace be upon him said this but Ibne Abbas was not paying attention to him in fact he was not even watching him, He( Tabiyee) said I do not see you hear my hadeeth, I am narrating the hadeeth of Prophet peace be upon him but you do not hear? Ibn Abbas replied: previously when we heard a person saying Prophet of Allah peace be upon him said this, our eyes also sees him quickly and our ears listened him, But when People started following wrong way(started narrating weak and fabricated ahadeeth) then we left listening ahadeeth except the ahadeeth we already knew.
(MUQADDIMAH SAHIH MUSLIM NUM 21)
NARRATION FROM TAWUS (TABIYEE),IBNE ABBAS SAID :-
We used to narrate hadeeth from Prophet peace be upon him when (people did not) lie on prophet peace be upon him, but when people started following wrong ways, we left narrating ahadeeth
(MUQADDIMAH SAHIH MUSLIM NUM 19)
After the death of Prophet peace be upon him people used to lie intentionally, and some people lied unintentionally because Fitnah was increasing, another proof for that are as follows :-
Yahya related to me from Malik from Musa ibn Uqba that Salim ibn Abdullah heard his father say, “Your claim that the Messenger of Allah, may Allah bless him and grant him peace, entered ihram from this desert of yours is not true, because he only entered ihram from the mosque, i.e. the mosque of Dhu’l-Hulayfa.”
MUWATTA MALIK (Book 20, Number 20.7.30)
Here Abdullah Ibne Omar ra is correcting his students that your claim is false regarding Prophet peace be upon him.So, It is proven directly from sahaba they never considered Mursal an evidence unless if someone narrates that from where he heard the hadeeth.
Muhammad bin Yahya bin saeed al Qattan Narrates from his Father that he said we have never seen righteous people lying in anything except in (narrating) hadeeth )same is narrated from Ibn Abi Attab) Imam Muslim said they do not lie deliberately but it appear on their tongue (unintentionally)
Righteous people who were not muhadditheen, they used to hear narrations and preach because they considered them authentic but in reality the narrations were false.
SOME SAYINGS OF MASTERS OF HADEET :-
ABDULLAH BIN MUBARAK AND REJECTION OF MURSAL
Imam Muslim narrates in Muqaddamah of Sahih Muslim:Muhammad said: I heard Aboo Ishaaq Ibraaheem Ibn ‘Easaa at-Taaqaanee saying: I said to ‘Abdullaah Ibnul-Mubaarak, “O Abaa ‘Abdur-Rahmaan! The hadeeth if which comes, “Certainly from al-birr (righteousness) after al-birr is to pray for your parents with your Prayer and to fast for them with your fast. ‘Abdullaah said, ‘O Abaa Ishaaq! From whom is this hadeeth?” I said, “It is from the hadeeth of Shihaab Ibn Kharaash.” He said, “He is trustworthy (thiqa). From whom does he narrate?” I said “From al-Hajjaaj Ibnud-Deenaar.” He said, “He is trustworthy. From whom does he narrate?” I said, “He said the Prophet (P.B.U.H) said.He (Ibn mubaarak) said, “O Abaa Ishaaq! Between al-Hajjaaj and the Prophet is a desert that would break the necks of the riding beasts! But there is no difference of opinion with regards to sadaqah (charity).
(MUQADDIMAH SAHIH MUSLIM CHAPTER NARRATING THE CHAIN IN DEEN )
IMAM MUSLIM SAID :-
The Mursal narrations according to me and the saying of the people of knowledge is that it is not evidence.
(MUQADDIMAH SAHEEH MUSLIM 1/24)
(IMAM AN NAWAWI AGREED WITH THIS STATEMENT OF IMAM MUSLIM SEE IRSHAAD PAGE 81)
IMAM HAAKIM SAID :-
According to Jamaah of Ahle Hadeeth and Fuqaha of Hijaaz, Mursal narrations are weak and not reliable and this is saying of Sa’eed bin Musayyib, Muhammad bin Muslim al Zuhri, Malik bin Anas, Abdul Rahman al Awza’ee, Muhammad bin Idrees al Shafi’ee, Ahmed bin Hanbal, And after them from the Fuqahaa of Madinah and upon this they have evidences from Qur’an and Sunnah of Prophet.
(AL MADHKAL PAGE 12)
IMAM TIRMIDHI SAID :-
When Hadeeth is Mursal then it not Sahih according to majority of Ahl e Hadeeth and many have said it as weak
(AL ILAL 4/397)
IBN ABEE HATIM SAID :-
I heard my father (Abu Haatim) and Abu Zur’ahsaying the mursal narrations are not evidence and evidence is only that which has an authentic and continuous/linked chain.”
(KITAAB AL-MARAASEEL PAGE 67)
IMAM KHATEEB AL-BAGHDADEE SAID :-
Muhammad ibn Idrees ash-Shaaf’iee and others amongst Ahlul-Ilm (People of Knowledge) it is not allowed to actupon them (ie Mursal narrations.) and said also this the Imaams and Scholarfrom amongst the preservers of hadeeth (Huffaadh al-Hadeeth) and thescrutinizers of narrations.”
(AL-KIFAAYAH FEE ILM AR-RIWAAYAH PAGE 384)
IMAM IRAQI SAID :-
Mostof the People of Hadeeth have rejected Mursal narrations because in that narration a narrator (which is not been mentioned by tabiee or any other) is unknown
(AL FAQEEH AL IRAQI PAGE 143 FATH UL BAQI,FATH UL-MUGEETH PAGE 69)
HAAFIDH IBN AS-SALAAH SAID :-
And what we have mentioned that mursal narrations cannot be deduced from and grading them to be weak then this is the position of the majority of the Preservers of Hadeeth (Huffaadh) and the scrutinizers of narrations and this is the opinion they have repeated in their works.”
(MUQADDIMAH PAGE 55)
HAAFIDH IBN AS-SALAAH FURTHER SAID :-
I say about mursal that its weak, which cannot be taken as evidence, Memorizers of hadeeth have consensus on this
(IKTISAAR ULOOM UL HADEET BY IMAM IBNE KHATIR UNDER MURSAL HADEET)
IMAM NAWAWEEE SAID :-
“Mursal narrations are not evidence according to me and according to the majority of the scholars of hadeeth, a group of jurists and the majority of the people of principles.”
(SHARH MUHAZZAB 1/103)
ALLAH SWT KNOWS BEST.