30 you shall count them from thirty years old and upward even to fifty years old—everyone who enters on the service, to do the work of the Tent of Meeting.
Numbers 4:30 Cross References - WEB
Numbers 4:3
3 from thirty years old and upward even until fifty years old, all who enter into the service to do the work in the Tent of Meeting.
Numbers 4:23
23 you shall count them from thirty years old and upward until fifty years old: all who enter in to wait on the service, to do the work in the Tent of Meeting.
Psalms 110:1-7
1 A Psalm by David. Yahweh says to my Lord, “Sit at my right hand, until I make your enemies your footstool for your feet.”
2 Yahweh will send out the rod of your strength out of Zion. Rule among your enemies.
3 Your people offer themselves willingly in the day of your power, in holy array. Out of the womb of the morning, you have the dew of your youth.
4 Yahweh has sworn, and will not change his mind: “You are a priest forever in the order of Melchizedek.”
5 The Lord is at your right hand. He will crush kings in the day of his wrath.
6 He will judge among the nations. He will heap up dead bodies. He will crush the ruler of the whole earth.
7 He will drink of the brook on the way; therefore he will lift up his head.
1 Timothy 6:11-12
2 Timothy 2:4
4 No soldier on duty entangles himself in the affairs of life, that he may please him who enrolled him as a soldier.