Slave of the Cross
That's what Abdul Saleeb means in Arabic: slave of the cross. His testimony is here, he is an MBB, that is, a convert from Islam. Here he describes himself before his conversion:
I thought of Islam as a faith with such high ideals that I did not consider myself worthy of the name Muslim but I wholeheartedly believed that Islam was God's last and most perfect religion for all mankind, based on God's final revelation, the Qur'an, and the prophet Muhammad, God's seal of prophethood. My view of other religions (especially Judaism and Christianity) was that although they were fundamentally the same since they had all been revealed by one God, they were all inferior to Islam because all of them had to various degrees corrupted the original message of their founding prophets, something that we as Muslims have not done.