ENOfficial
Anas b. Malik told of God’s messenger saying when Ramadan began, “This month has come to you, and it contains a night which is better than a thousand months. He who is deprived of it is deprived of all good, but only those who are denied prosperity are deprived of it." Ibn Majah transmitted it.
Source: sunnah.com
Other translations
Arabic
وَعَنْ أَنَسِ بْنِ مَالِكٍ قَالَ: دَخَلَ رَمَضَانُ فَقَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «إِنَّ هَذَا الشَّهْرَ قَدْ حَضَرَكُمْ وَفِيهِ لَيْلَةٌ خَيْرٌ مَنْ أَلْفِ شَهْرٍ مَنْ حُرِمَهَا فَقَدْ حُرِمَ الْخَيْرَ كُلَّهُ وَلَا يُحْرَمُ خَيْرَهَا إِلَّا كل محروم» . رَوَاهُ ابْن مَاجَه
sunnah.com