It's more about if in the context you want to emphasize his godliness or his humanity.

"Christ Jesus" would be more descriptive of your intention if you're talking about his capacity to do things like absolve you of sin. "Jesus Christ" would be more explicit about your intention if you were talking about him getting tired and sleeping.

Similarly to "affect" and "effect", some people use it correctly... but have no idea why or what the rules are. Others use it wrongly.

In this case... the original author may have consciously (or unconsciously) wanted to emphasis that the son of God (as opposed to the son of a carpenter) is the guy. Or he maybe just did it to sound fancy.

Edit:

What I really wanna know is in the picture, who has the higher battlefield rank?? There are like 3 people on the planet who I'd trust an analysis of that from, and you're one.