Al-A'raf - 7:205

وَاذْكُر رَّبَّكَ فِي نَفْسِكَ تَضَرُّعاً وَخِيفَةً وَدُونَ الْجَهْرِ مِنَ الْقَوْلِ بِالْغُدُوِّ وَالآصَالِ وَلاَ تَكُن مِّنَ الْغَافِلِينَ
[7:205]
And remember your Lord within yourself humbly and fearing and in a voice not loud in the morning and the evening and be not of the heedless ones.
And do thou (O reader!) Bring thy Lord to remembrance in thy (very) soul, with humility and in reverence, without loudness in words, in the mornings and evenings; and be not thou of those who are unheedful.
And do thou (O Muhammad) remember thy Lord within thyself humbly and with awe, below thy breath, at morn and evening. And be not thou of the neglectful.