The theme of this book is the light cast by the activities of Joshua, in possessing the land which God gave to Israel, on the present understanding and enjoyment of all that the Christian believer is brought into as a result of the death of Christ -- now risen and ascended.
For the Israelite nation, escape from Egypt was followed by troubled years in the wilderness before reaching Canaan, the Promised Land. But, having arrived, they were only able to take possession of those parts of it on which they could walk; and this meant warfare. Some see the Christian experience mirrored in this: a constant daily struggle, with little encouragement until the wilderness and warfare experience is ended and rest is obtained eternally in Heaven -- the Father's house -- the promised land.
The author demonstrates clearly from Scripture that enjoyment of the Christian's eternal inheritance begins now. "To know the love of Christ is the corn and the wine, the milk and honey, the wealth and plenty of the Christian's Canaan. It is the pure delight of a day which will know no evening shade."