Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
bayhaqi:7282al-Shaykh

[Machine] And Al-Hasan Al-Basri said about a man who was obligated to pay zakat but did not pay it until his wealth was gone, he said: "It is a debt upon him until he fulfills it." Abu Al-Husayn Ibn Bashran informed us that Isma'il Ibn Muhammad narrated to us, who was informed by Sa'dan, who was informed by Mu'adh Ibn Mu'adh, who heard it from Ash'ath, who narrated it from Al-Hasan.  

البيهقي:٧٢٨٢قَالَ الشَّيْخُ

وَقَالَ الْحَسَنُ الْبَصْرِيُّ فِي رَجُلٍ وَجَبَتْ عَلَيْهِ الزَّكَاةُ فَلَمْ يُزَكِّ حَتَّى ذَهَبَ مَالُهُ قَالَ هُوَ دَيْنٌ عَلَيْهِ حَتَّى يَقْضِيَهُ أَخْبَرَنَاهُ أَبُو الْحُسَيْنِ بْنُ بِشْرَانَ أنبأ إِسْمَاعِيلُ بْنُ مُحَمَّدٍ ثنا سَعْدَانُ ثنا مُعَاذُ بْنُ مُعَاذٍ عَنْ أَشْعَثَ عَنِ الْحَسَنِ فَذَكَرَهُ