It's not exactly clear what you think the difference is between "through" and "across".
A resistor has two wires. Electric current that flows into one wire, continues <em>through</em> the entire body of the resistor and out <em>through</em> the other wire. If there's a crack or break anywhere along the body of the resistor, the circuit will be 'open' and the current will stop flowing.
Now, if you were to connect a <em>voltmeter</em> between the ends of the resistor, the meter would measure and indicate the difference in electric potential between those two points. That would be called the voltage '<u><em>across</em></u>' the resistor. Numerically, it would be equal to the product of the resistor's resistance and the current through it.
