Sahih al-Bukhari 6596
Narrated `Imran bin Husain:
A man said, "O Allah's Messenger (ﷺ)! Can the people of Paradise be known (differentiated) from the people 
of the Fire; The Prophet (ﷺ) replied, "Yes." The man said, "Why do people (try to) do (good) deeds?" The 
Prophet said, "Everyone will do the deeds for which he has been created to do or he will do those 
deeds which will be made easy for him to do." (i.e. everybody will find easy to do such deeds as will 
lead him to his destined place for which he has been created).
حَدَّثَنَا آدَمُ، حَدَّثَنَا شُعْبَةُ، حَدَّثَنَا يَزِيدُ الرِّشْكُ، قَالَ سَمِعْتُ مُطَرِّفَ بْنَ عَبْدِ اللَّهِ بْنِ الشِّخِّيرِ، يُحَدِّثُ عَنْ عِمْرَانَ بْنِ حُصَيْنٍ، قَالَ قَالَ رَجُلٌ يَا رَسُولَ اللَّهِ أَيُعْرَفُ أَهْلُ الْجَنَّةِ مِنْ أَهْلِ النَّارِ قَالَ ‏"‏ نَعَمْ ‏"‏‏.‏ قَالَ فَلِمَ يَعْمَلُ الْعَامِلُونَ قَالَ ‏"‏كُلٌّ يَعْمَلُ لِمَا خُلِقَ لَهُ ـ أَوْ لِمَا يُسِّرَ لَهُ‏"‏ ‏.‏