The Difference Between Profession and Confession

"If I profess with the loudest voice  and clearest exposition every portion of the truth of God except precisely that little point which the world and the devil are at that moment attacking, I am not confessing Christ, however boldly I may be professing Christ.
Where the battle rages, there the loyalty of the soldier is proved, and to be steady on all the battlefield  besides is mere flight and disgrace if he flinches at that point."
 -formally attributed to Martin Luther
It is now believed that this quote is by Elizabeth Rundle Charles, from her book The Chronicles of the Schoenberg Cotta Family (Thomas Nelson, 1864).

"Whosoever therefore shall confess me before men, him will I confess also before my Father which is in heaven. But whosoever shall deny me before men, him will I also deny before my Father which is in heaven." Matthew 10:33