وَالْوَقْتُ وَاعْتِقَادُ دُخُولِهِ
Prayer is not begun on mere unresolved doubt about whether its time has entered. The worshipper must know or have a reliable predominant belief that the time has begun. If one begins on pure doubt and only later discovers the time had in fact entered, that discovery does not repair the defective start under the rule taught here.