By ‘earnestness’ James means what today- due greatly to the influence of John Piper- would be dubbed ‘passion.’ He calls for a whole-hearted devotion to the labor of saving souls, which he is careful to define as including both seeing people come to faith and laboring for their sanctification so that they persevere (previous comment on this point).
Of such earnestness James also writes:
“Good preaching and good shepherding are quite compatible with each other, and he who is in earnest will combine both.” (149)This is a needed point. If we are in earnest about the salvation of souls we must labor in the teaching of the Word and in the careful oversight of the souls of our flock. These two activities cannot rightly be divorced. Careful oversight may not make us famous since people cannot download our oversight onto their iPods, but our preaching cannot be what it ought to be without this oversight.