What makes a miracle miraculous?

5 After the Philistines had captured the ark of God, they took it from Ebenezer to Ashdod. 2 Then they carried the ark into Dagon’s temple and set it beside Dagon. 3 When the people of Ashdod rose early the next day, there was Dagon, fallen on his face on the ground before the ark of the Lord! They took Dagon and put him back in his place. 4 But the following morning when they rose, there was Dagon, fallen on his face on the ground before the ark of the Lord! His head and hands had been broken off and were lying on the threshold; only his body remained. 5 That is why to this day neither the priests of Dagon nor any others who enter Dagon’s temple at Ashdod step on the threshold. 6 The Lord’s hand was heavy on the people of Ashdod and its vicinity; he brought devastation on them and afflicted them with tumors (1 Sam 5:1-6).

Since the Bible nowhere define a miracle, philosophers and theologians come up with their own definitions. Two popular definitions are a "violation of natural law" and an effect which bypasses natural processes. 

Up to a point, these can both be useful definitions. There are some biblical events which fit those definitions. But there are many "miraculous" events in Scripture which slip through the sieve. 

The issue is important in debates over cessationism. Cessationism requires a very narrow definition of what constitutes a miracle. Problem is, the definition is so tightly drawn that it excludes many Biblical events which are impressive candidates for the miraculous. Shouldn't that inform our concept of the miraculous? 

Consider the example from 1 Samuel:

i) An idol tipping over doesn't violate any law of nature, does it? Likewise, it doesn't necessarily bypass second causes. By the same token, an idol breaking on contact with a hard surface isn't clearly a violation of natural law. And that doesn't necessarily (or even probably) bypass natural processes. It's not unusual for things to fall over or break. 

By the same token, the punitive pestilence doesn't violate a law of nature or bypass natural processes. To the contrary, it seems to exploit preexisting pathogens. Redirects them. 

ii) So should we demote these events to something less than miraculous? We could say it's providential. And there's nothing necessarily wrong with that classification.

But that fails to distinguish between events that happen automatically, and events that swim against the current (as it were). Left to its own devices, natural cause and effect wouldn't be that discriminating. 

iii) What makes this miraculous is twofold:

a) The specificity in time and place. It's not idols falling down generally, or idols breaking generally. Rather, this happened when a rival religious object was brought into the heathen temple.

And this happened back-to-back. Even if the first occurrence was merely coincidental, what about two nights in a row? Notice, too, that the second occurrence doesn't merely repeat the first occurrence, but intensifies the result. 

Not only the timing, but the placement. The idol falls down right in front of the ark. 

b) This, in turn, brings us to the symbolism of the event. Minimally, the posture of the fallen idol signifies a pagan "god" worshipping the one true God. That's quite ironic.

In addition, it probably represents the true God subduing a false god–like a conqueror who subjugates the defeated king. Public humiliation. This is further reinforced by mutilating the idol. 

Finally, the fact that the idol is decapitated and amputated symbolizes the ignorance and impotence of pagan divinities. Know-nothing, do-nothing deities. 

This could all happen through natural mechanisms, yet it can still be miraculous.