We are from Allah and to Him we are returning, a Quranic Verse said on the death
الَّذِينَ إِذَا أَصَابَتْهُمْ مُصِيبَةٌ قَالُوا إِنَّا لِلَّهِ وَإِنَّا إِلَيْهِ رَاجِعُونَ {156}
Who, when a difficulty befalls them, are saying: We are from Allah, and we are returning to Him [2:156]
و عنه: عن علي بن محمد، عن صالح بن أبي حماد، رفعه، قال
And from him, from Ali Bin Muhammad, from Salih Bin Abu Hamaad, raising it, said,
جاء أمير المؤمنين (عليه السلام) إلى الأشعث بن قيس يعزيه بأخ له، يقال له: عبد الرحمن، فقال له أمير المؤمنين: «إن جزعت فحق الرحم أتيت، و إن صبرت فحق الله أديت، على أنك إن صبرت جرى عليك القضاء و أنت محمود، و إن جزعت جرى عليك القضاء و أنت مذموم
Amir Al-Momineen-asws went to Al-Ash’as Bin Qays to console him for (the death of) his brother, called Abdul Rahman. Amir Al-Momineen-asws said to him: ‘I-asws came to you for the grief which is the right of the womb (relationship), and if you are patient then the right of Allah-azwj is fulfilled, upon that if you were patient the Judgment would follow you and you would be a praised one, and if you grieve then the Judgment would follow you and you would be a condemned one’.
فقال له الأشعث: إنا لله و إنا إليه راجعون! فقال أمير المؤمنين (عليه السلام): «أ تدري ما تأويلها؟» فقال الأشعث: أنت غاية العلم و منتهاه. فقال له: «أما قولك: إنا لله، فإقرار منك بالملك، و أما قولك: و إنا إليه راجعون، فإقرار منك بالهلاك
Al-Ash’as said to him-asws, ‘We are from Allah and we are returning to Him [2:156]’. So Amir Al-Momineen-asws said: ‘Do you know what its interpretation is?’ So, Al-Ash’as said, ‘You-asws are the height of the Knowledge and its limit’. So, he-asws said to him: ‘As for your saying we are from Allah, so it is acceptance from you of the King-azwj, and as for your saying and we are returning to Him, so it is the acceptance from you of your destruction (death)’.[1]
[1] الكافي 3: 261/ 40