What's the easy way to find this problem?

[Kenton H. Shepard, CMI]

Grab the gas pipe as you enter the crawlspace. Kind of the opposite of bonding the gas pipe, eh?

[Jeffrey R. Wicklander]

was it live?

[Jeffrey R. Pope]

If the gas line is bonded as it should be, then a live ungrounded conductor would trip the breaker when/if it came in contact with the piping.

In this case, it appears to be an EGC, which is already "in contact" with the piping if it has been properly bonded.

In any case, this is simply "an open junction box." The EGC's need to be tied together and the box needs to be covered.