In Exodus 17:10, they signify divine truth in successive order, that is, divine truth immediately from the Lord, mediately from Him, and divine truth proceeding mediately from this. (Arcana Coelestia 8602)

8601. 'And Joshua did as Moses said to him' means that the truth which engages in conflict acted as directed by Divine Truth. This is clear from the meaning of 'doing' as putting into effect; from the representation of 'Joshua' as truth that engages in conflict, dealt with just above in 8595; and from the meaning of 'as Moses said to him' as, as directed by Divine Truth, since 'Moses' represents Divine Truth, and 'said' means being directed by it.