Arabic text
عَنْ سَهْلِ بْنِ مُعَاذِ بْنِ أَنَسٍ عَنْ أَبِيهِ قَالَ: قَالَ رَسُولُ اللهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «مَنْ أَكَلَ طَعَامًا فَقَالَ: الحَمْدُ لِلَّهِ الَّذِي أَطْعَمَنِي هَذَا وَرَزَقَنِيهِ مِنْ غَيْرِ حَوْلٍ مِنِّي وَلاَ قُوَّةٍ، غُفِرَ لَهُ مَا تَقَدَّمَ مِنْ ذَنْبِهِ».
Translation
Sahl ibn Mu‘ādh ibn Anas related from his father that the Messenger of Allah (may Allah's peace and blessings be upon him) said: "Whoever eats food and says 'Alhamdulillah al-ladhi at‘amani hadha wa razaqneih min ghayri hawl li wala quwwah (Praise be to Allah who fed me and provided me with this food through no might or power on my part)', his past sins will be forgiven."
Explanation
The Prophet (may Allah's peace and blessings be upon him) urges one who eats food to praise Allah, for a person has no power to bring food or eat it except through Allah Almighty and His help. Then, he (may Allah's peace and blessings be upon him) gives glad tidings to one who says these words that he deserves the forgiveness of Allah for his past minor sins.
Source: HadeethEnc.com