The Holy Spirit does not tell us the answer to this question. Two factors, however, suggest that Nehemiah’s prayer was public. First, he utters his prayer in response to Sanballat’s very public derision of the people and their God. If in his memoirs Nehemiah can relate his prayerful response to Sanballat’s public derision, it stands to reason that his own response was public as well. Second, and more tellingly, the people continued to build (Nehemiah 4:6). Their response to the derision they heard makes sense if their leader publicly directed them to the care of their God. He could effectively do so through his public prayer.
5 Do not cover their guilt, and let not their sin be blotted out from your sight, for they have provoked you to anger in the presence of the builders.