(Al-Insan) 76 : 5
إِنَّ الْأَبْرَارَ يَشْرَبُونَ مِنْ كَأْسٍ كَانَ مِزَاجُهَا كَافُورًا

Indeed, virtuous shall drink from a cup having the flavor of camphor.

Here mentioned virtuous are those ‘grateful’ mentioned in the verse 3, includes forerunners- who enter the Paradise without trial- and heedful- who will enter Paradise after Trial. They are only one among each thousand. Read together the verses 2: 177; 3: 193 and 32:15-16 in the Reminder, safeguarded by the Lord of all worlds.