I'm working through my Christmas messages today and in a couple of weeks I'll preach on Luke 2:9-10
The Holy Bible : New International Version, electronic ed., Lk 2:9-10 (Grand Rapids: Zondervan, 1996, c1984).
By way of practical application we can note that upon seeing the angel of the Lord the shepherds were terrified. And the angel addresses their fear.
At this point we can stop and ask how we would address someone who was consumed with terror or abject fear. Most of us would tend to address the fear head on and provide logical or practical antidotes to the fear. Our message would probably eventually get around to one of two things - 1) don't worry you have nothing to fear, or 2) take courage, you can handle this. I suppose we could go with a third - "you're right, this is going to be as bad as you think it is and you are probably gonna die, but hey, it's Christmas season and I'm trying to keep things on a more hopeful note.
The opposite of fear is usually courage so unless we took the "you have nothing to fear" route, most of us would take the "have courage" route. But the angel takes the "joy" route here.
This is not to say that courage is unnecessary, but I think we ought to pay some attention to the fact that joy is offered in place of fear here and consider the relationship between joy and fear. Could it be that joy is the remedy for fear? And could it be that joy is the foundation for courage?
I don't mean this in a Bobby McFerrin "don't worry be happy" way - where we say "oh quit worrying and be happy." In this case the angel was pointing to a real event as the source of joy. In other words, there joy was not to come through a change in their state of mind. Their joy was to come through consideration of a real event - the incarnation. Rather than trying to work themselves into a state of joy, the shepherds needed to consider the implications of the incarnation, and this would produce joy, and I would extrapolate from there to say that this would lead to courage.
And applying this to us I suggest that, when somneone is struggling with fear the answer is not to tell them to "take courage" as if they can suddenly turn on the courage switch in their minds. The antidote to fear is "find joy." But this is also not simply telling them to change their state of mind. The antidote is to "find joy - by considering who Christ is and what He has done."
Death and God are the two most fearful things that humans face. Death because, well it's death, it's final and it is what people in general fear most. In the Bible when people encountered God or one of his messengers the usual response was similar to the shepherds - terror.
Jesus has overcome both - He has defeated death and He has removed the barriers of sin that give us reason to fear an encounter with God.
Hence, since Christ has removed the sources of our two greatest fears it would seem reasonable that His redemption is the antidote to all our lesser fears, and every fear short of death or God is a lesser fear. In other words, the worst that can happen to anyone can't happen to those who are in Christ. Thus based upon His objective work on the cross we have reason for joy and thus ability to find freedom from fear, and thus ability to find courage.