do you believe in God, yourself?" "I believe in Russia.... I believe in her orthodoxy.... I believe in the body of Christ.... I believe that the new advent will take place in Russia.... I believe..." Shatov muttered frantically. "And in God? In God?" "I... I will believe in God."
"I believe in the Body of Christ" meaning the Christian people. He does not yet believe in God, but he wants to because he thinks a belief in God is necessary for the future success of Russia.