2 Chronicles 31:16
without regard to their genealogical registration, to the males from thirty years old and upward—everyone who entered the house of the Lord for his daily obligations—for their service in accordance with their duties by their divisions;
Ezra 3:4
                            They celebrated the Feast of 
Leviticus 21:22-23
He may eat the food of his God, both of the most holy and of the holy things,
1 Chronicles 23:3
The Levites thirty years old and upward were counted, and their number man by man was 38,000.
Treasury of Scripture Knowledge
Summary
                            Beside their genealogy of males, from three years old and upward, even unto every one that entereth into the house of the LORD, his daily portion for their service in their charges according to their courses;                        
                    His daily
Bible References
His daily
                                        Leviticus 21:22                                        
                                                            
                        He may eat the food of his God, both of the most holy and of the holy things,