Jami` at-Tirmidhi 2593
From Anas, that the Messenger of Allah (s.a.w) said – Hisham (one of the narrators) narrated it:
“Some will exit the Fire,” Shu`bah (another narrator) narrated it: 'Remove from the Fire whoever said La ilaha illallah and had good in his heart equal to the weight of a grain of barley. Remove from the Fire anyone  who said La Ilaha illallah and had good in his heart equal to the weight of a grain of wheat. Remove from the Fire anyone  who said La ilaha illallah and had good in his heart equal to the weight of a speck.” And Shubah said: “What is equal to the weight of a light piece of corn.” (Sahih) Other chains report similar narrations.
حَدَّثَنَا مَحْمُودُ بْنُ غَيْلاَنَ، حَدَّثَنَا أَبُو دَاوُدَ، حَدَّثَنَا شُعْبَةُ، وَهِشَامٌ، عَنْ قَتَادَةَ، عَنْ أَنَسٍ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ - قَالَ هِشَامٌ ‏"‏ يَخْرُجُ مِنَ النَّارِ ‏"‏ ‏.‏ وَقَالَ شُعْبَةُ ‏"‏ أَخْرِجُوا مِنَ النَّارِ مَنْ قَالَ لاَ إِلَهَ إِلاَّ اللَّهُ وَكَانَ فِي قَلْبِهِ مِنَ الْخَيْرِ مَا يَزِنُ شَعِيرَةً أَخْرِجُوا مِنَ النَّارِ مَنْ قَالَ لاَ إِلَهَ إِلاَّ اللَّهُ وَكَانَ فِي قَلْبِهِ مِنَ الْخَيْرِ مَا يَزِنُ بُرَّةً أَخْرِجُوا مِنَ النَّارِ مَنْ قَالَ لاَ إِلَهَ إِلاَّ اللَّهُ وَكَانَ فِي قَلْبِهِ مِنَ الْخَيْرِ مَا يَزِنُ ذَرَّةً ‏"‏ ‏.‏ وَقَالَ شُعْبَةُ ‏"‏ مَا يَزِنُ ذُرَةً ‏"‏ ‏.‏ مُخَفَّفَةً ‏.‏ وَفِي الْبَابِ عَنْ جَابِرٍ وَعِمْرَانَ بْنِ حُصَيْنٍ ‏.‏ قَالَ أَبُو عِيسَى هَذَا حَدِيثٌ حَسَنٌ صَحِيحٌ ‏.‏