I believe it was 1,000 who were not fearful ... of the 1,000, God chose the 300.
As far as not trembling with fear ... I do not know of anyone who is involved in military conflict who is 100% comfortable in the engagement. Even in the record in Judges 7, Gideon had some trepidation:
Judges 7:9-15
9 And it came to pass the same night, that the LORD said unto him, Arise, get thee down unto the host; for I have delivered it into thine hand.
10 But if thou fear to go down, go thou with Phurah thy servant down to the host:
11 And thou shalt hear what they say; and afterward shall thine hands be strengthened to go down unto the host. Then went he down with Phurah his servant unto the outside of the armed men that were in the host.
12 And the Midianites and the Amalekites and all the children of the east lay along in the valley like grasshoppers for multitude; and their camels were without number, as the sand by the sea side for multitude.
13 And when Gideon was come, behold, there was a man that told a dream unto his fellow, and said, Behold, I dreamed a dream, and, lo, a cake of barley bread tumbled into the host of Midian, and came unto a tent, and smote it that it fell, and overturned it, that the tent lay along.
14 And his fellow answered and said, This is nothing else save the sword of Gideon the son of Joash, a man of Israel: for into his hand hath God delivered Midian, and all the host.
15 And it was so, when Gideon heard the telling of the dream, and the interpretation thereof, that he worshipped, and returned into the host of Israel, and said, Arise; for the LORD hath delivered into your hand the host of Midian.
in vs 10, God told Gideon that if he had any fear, he should take Phurah and go down to listen to the Midianites.
in vs 13, Gideon went ... indicating that he did have some fear.
I do not believe caution is a bad thing. God gave mankind emotions when He created, formed, made Adam. On Day 6, God saw every thing that he had made, and, behold, it was very good (Gen 1:31).
The problem with our emotions is when we allow our emotions to rule over us. When we fear, this is a warning ... fear should cause us to be careful ... nothing wrong with that ... fear should point us to God Who is our sufficiency in every situation. However, when we allow our fear to dictate to the point where we do not trust in God, that is not good.
Maybe alarm or unease would be a better word to use. fear brings to mind a failure to trust in God.
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