Coping with big success is a challenge for bands of any genre. For MercyMe, the task was to prove that their debut Christian radio hit “I Can Only Imagine” was more than an inspirational fluke, andSpoken For gave ample evidence of the group’s rock-solid commitment to its mission and its music. Bart Millard shows considerable versatility as a vocalist, conveying child-like humility on the title track, lighthearted joy on “All of the Above” and preacher-like authority on “Go.” MercyMe’s sonic identity is somewhat blurred on this album — one minute, they sound like a genial country-pop group (“The Change Inside of Me”), the next a moody British rock combo (“Come One, Come All,”) or an old-fashioned gospel outfit (“The Love of God”). But no matter. Lyrically-outstanding tracks like as “There’s a Reason” (a stirring reaffirmation of faith in a post-9/11 world) and “Crazy” (a defiant, poetic statement of spiritual resistance) make it clear MercyMe intends to be a force within Christian music for years to come.