Read 1 Samuel 21
For an understanding one must go back to Leviticus 24. God gave commandment that twelve loaves of bread were to be placed on a special table in the holy place on each Sabbath. When the bread was exchanged, the older loaves were for the priests and their families. It was considered a holy offering to God. What the bread in this case symbolizes has been debated for centuries, I think it safe to say the number twelve being the tribes of Israel. Aside from that, I think it might mean that there is always food in the presence of God, albeit sometimes it is spiritual and not physical. As this was considered a holy food, those eating it needed to be pure, having abstained from sex.
So there are a couple of aspects here, the bread was holy, to be consumed by the priest, but in this case, as David and his men may have been without food for some time, it is proper and lawful for the priest to give the bread to the men. We are not told how many men were there or how many loaves but an idea on how large the loaves were can be found in the recipe. Each loaf had about .9 gallon of flour, the actual shape was dictated by the baking form which no-one today knows what that looked like. If one were to simply grind flour and make a loaf from the instructions in Torah, it could make a slab about 15 inches square and 1 inch thick. Imagine a large square deep dish pizza dough.
Today's workout. Grapevine, pull up, burpee, row, jump rope, T. 6 moves 36 intervals