We clearly are not to take these words literally, as if Nehemiah did not sleep or fulfill his task before the king; instead, they describe sustained, persistent prayer (Luke 18:3–4). The only other place in the Old Testament where the phrase day and night
occurs in relation to prayer is in Solomon’s prayer at the dedication of the temple (2 Chronicles 6:19–20; 1 Kings 8:28–29). By borrowing these words from Solomon’s prayer, Nehemiah is again holding God to his own promise always to hear (2 Chronicles 7:15).
6 let your ear be attentive and your eyes open, to hear the prayer of your servant that I now pray before you day and night for the people of Israel your servants, confessing the sins of the people of Israel, which we have sinned against you. Even I and my father’s house have sinned.