Man cannot "find" God; only God can initiate a calling. The world, including most of physical Israel, is consigned to unbelief until later in God's plan, yet most modern Israelites would say they know God or believe in Him. Romans 10:12-15 describes how God generally introduces people to Himself, though they may suppose they initiated contact with Him by "calling on the name of the Lord." Men must hear of Him through a preacher - and one whom God has sent, not one that is self-proclaimed.
Martin G. Collins
Basic Doctrines: Faith Toward God
God has set up a system to call, convert, and educate a people for Himself. They are a minority, very few in number. They are not mighty, noble, and learned, but the weak of the world. God calls them and gives them His Spirit and teachers to help them understand. Of all people on earth, only they have a chance to understand the Bible.
Other Forerunner Commentary entries containing Romans 10:13:
1 Corinthians 1:18-21