Paul on Tithing Series: Military Analogy

Do ye not know that they which minister about holy things
live of the things of the temple?

 and they which wait at the altar are partakers with the altar?

Even so hath the Lord ordained that they
which preach the gospel should live of the gospel.

1 Corinthians 9:13,14

Military Analogy

Who goeth a warfare any time at his own charges?
1 Corinthians 9:7
Who would go to war for an army if he had to supply his own food, weapons, ammo, supplies & uniforms?