Those who are Mukallaf (charged) with the Ahkaam (of Islaam) are all of the people and for that reason it has been said in regards to the definition of the Hukm Ash-Shar’iy that it is: “The address of the legislator related to the actions of the ‘Ibaad” and the ‘Ibaad refers to the people whether they are Muslim or Kuffaar (disbelievers).

The Daleel for that is as follows:

1 – Allah (swt) says:

And Allah Ta’Aalaa said:

So the ‘Naas’ (people/mankind) as a whole have been addressed with the Deen of Islaam and it is a duty for the Muslims to convey Islaam to them in an eye-catching manner. This is just as the Messenger of Allah (saw) did when he sent messengers and letters to the well-known and prominent kings and rulers existing at his time inviting them to embrace Islaam and to submit to the Islamic State.

2 – The Qur’aan addressing the people or mankind as a whole:

Allah (swt) said:

What is meant by ‘Ibaadah (worship) here is its general meaning which is to follow the commands of Allah and keep away from what He has forbidden. Allah (swt) said

And Allah (swt) said:

This was mentioned in the context of asking the disbelievers about their branch actions like the Salaah and their punishment for what they didn’t perform, as shown in the following Qawl of Allah Ta’Aalaa connected to that in the same Soorah:

These Aayaat therefore indicate that they are Mukallafeen (charged) with the Ahkaam Al-Furoo’iyah (branch rulings) just as they are Mukallafoon in respect to the ‘Aqaa’id (beliefs). Had they not been charged and accountable for the Furoo’ (branches) Allah would not have threatened them with a severe threat of punishment for leaving and not performing them.

Consequently, the people (An-Naas) in their entirety are addressed with the Islamic Sharee’ah as a whole including its Usool and Furoo’ i.e. Aqaa’id and Ahkaam. And Allah (swt) will punish them for not having Imaan and for not undertaking the obligatory actions.