It’s just what you learnt in the field
1 Samuel 17:34-37 NLT But David persisted. “I have been taking care of my father’s sheep and goats,” he said. “When a lion or a bear comes to steal a lamb from the flock, I go after it with a club and rescue the lamb from its mouth. If the animal turns on me, I catch it by the jaw and club it to death. I have done this to both lions and bears, and I’ll do it to this pagan Philistine, too, for he has defied the armies of the living God! The Lord who rescued me from the claws of the lion and the bear will rescue me from this Philistine!”
David spent many years training for what was ahead for him. He had fought off lions and bears, even extracting the lambs from their mouths. Nothing was too big for him out in his field. He had a confidence and authority that went way beyond his size and natural abilities.
David also had a dependence on a God that was sure to deliver him every time without fail. So when it comes to his big moment to shine, his experience in his field along with his faith in his God sends the giant crashing down with a single stone.
God has been training you and preparing you in your field right for this moment. While you have been fighting off enemies and practising your skills, you never would have comprehended how this has equipped you for a time such as this. Your faith has been stretched but your confidence steadily growing.
The field or area you have been developing in is simply the lead up to a great victory that awaits you.
This is the big one. So gather together everything He has taught you in your training time and accurately fire your stone at the forehead of the big fella.