As a Manager I can say with certainty that Abraham did not personally train 318 men. As he prospered he likely trained a core of servants of between ten or twenty. That's about all a person can do one-on-one. As his holdings grew and more servants were added, this core would have trained the new crew. Twenty well-trained supervisor/servants could have each had twenty more; 400 men.
Also, let's not forget Moses' arrangement. His supervisors each only had five or ten people under them.
Exodus 18:21 NIV But select capable men from all the people—men who fear God, trustworthy men who hate dishonest gain—and appoint them as officials over thousands, hundreds, fifties and tens.
Now, with the elders, they are expected to keep up on their family responsibilities, be a provider, keep up on all the Watchtower demands, AND be a shepherd. Impossible. In my opinion, they are muzzled labourers.
- 1 Corinthians 9:9
For it is written in the law of Moses, thou shalt not muzzle the mouth of the ox that treadeth out the corn. Doth God take care for oxen?
1 Corinthians 9:8-10 (in Context) 1 Corinthians 9 (Whole Chapter) - 1 Timothy 5:18
For the scripture saith, thou shalt not muzzle the ox that treadeth out the corn. And, The labourer is worthy of his reward.
1 Timothy 5:17-19 (in Context) 1 Timothy 5 (Whole Chapter)