Where the responsibility stops
Umar argued with Abu Bakr about it and lost.
The words
فَمَنْ قَالَهَا فَقَدْ عَصَمَ مِنِّي مَالَهُ وَنَفْسَهُ إِلاَّ بِحَقِّهِ، وَحِسَابُهُ عَلَى اللَّهِ
Fa-man qālahā faqad ʿaṣama minnī mālahu wa nafsahu illā bi-ḥaqqih, wa ḥisābuhu ʿalā-Llāh
The pronunciation above covers the opening of this passage, not all of it
Whoever says it has protected his wealth and his life from me, except by its right. And his reckoning is with Allah.
Where this comes from
The final clause is the one that settles it. What a person owes outwardly is one question. What is inside them is explicitly handed to somebody else.
The full narration
Narrated Abu Huraira:When Allah's Messenger (ﷺ) died and Abu Bakr became the caliph some Arabs renegade (reverted to disbelief) (Abu Bakr decided to declare war against them), `Umar, said to Abu Bakr, "How can you fight with these people although Allah's Messenger (ﷺ) said, 'I have been ordered (by Allah) to fight the people till they say: "None has the right to be worshipped but Allah, and whoever said it then he will save his life and property from me except on trespassing the law (rights and conditions for which he will be punished justly), and his accounts will be with Allah.' " Abu Bakr said, "By Allah! I will fight those who differentiate between the prayer and the Zakat as Zakat is the compulsory right to be taken from the property (according to Allah's orders) By Allah! If they refuse to pay me even a she-kid which they used to pay at the time of Allah's Messenger (ﷺ) . I would fight with them for withholding it" Then `Umar said, "By Allah, it was nothing, but Allah opened Abu Bakr's chest towards the decision (to fight) and I came to know that his decision was right
Source
Ṣaḥīḥ al-Bukhārī · 1399
- Recorded in Ṣaḥīḥ al-Bukhārī, whose narrations are accepted as authentic