Fathwa - The order to differ from the Jews concerning fasting the day of ‘Aashooraa’ came duringthe last period of the life of the Prophet

Question
Assalaamu alaikum, When Rasoolullah )salla Allahu alayhi wa sallam(
came to al-Madinah, he saw the Jews fasting Ashura and thus he
commanded the Muslims to fast that day too. In hislast year, he said
that if he was to live another year, then he would fast the 9th too,
so to differentiate from the Jews. Does that mean that the order of
differentiating from the Jews and Christians came in the last year?
Jazakum Allahu khairan
Answer
All perfect praise be to Allaah, The Lord of the Worlds. I testify
that there is none worthy of worship except Allaah, and that
MuhammadisHis slave and Messenger.
The order to differ from the Jews concerning fasting the day of
'Aashooraa')10thof Muharram( such that one fasts another day along
with it ]whether before or after it[ came during the last period of
the life of the Prophet,, as thequestioner mentioned.
Ibn Hajarfrom the Shaafi'i school of jurisprudence said in his
bookFat-h Al-Baari,"There is another narration reported by Ahmadthat
was narrated by Ibn 'Abbaasin which the Prophetsaid: ''Fast on the day
of 'Ashooraa' and be different from the Jews, fast one day before it
or after it." This was towards the end of his life. The Prophetused to
like to act in accordance with the People of the Book in matters where
he was not ordered to do otherwise – especially when this would be
contradicting the practice of the idolaters. However, when Makkah was
conquered and Islambecame widespread, the Prophetwould differ from the
People of the Book, as was narrated in a Saheeh Hadeeth)authentic
narration(. Therefore the Prophetdid the same as the People of the
Book did initially, and said: 'We areworthier of Moosa)Moses(than
them.' Then heliked to differ from them and ordered us to add one day
before 'Aashooraa' or after it in order to be different from them."]
Allaah Knows best.