In Amos 3:15, this signifies the sensuous things of the natural man. (Apocalypse Explained 1146[3])

8606. 'And when he let down his hand' means whenever their faith looked downwards or away from the Lord towards self and the world. This is clear from the explanation just above in 8604. The reason why faith that looks to the Lord is a winner is that in these circumstances the Lord does the fighting; for the Lord constitutes faith because it is received from Him. But the reason why faith which looks away from the Lord towards self and the world is a loser is that then the person does the fighting all alone.