Early in my walk, I felt afraid of these doubts, especially when the world told me one thing and the Bible told me another. Each time, I stepped out in faith, though not without some fear, to look deeper not only into what God tells me but also deeper into what the world was telling me. Time and time again, this played out. After about 10 years of this (somewhere along the way), it's no longer that I do so with fear that I might lose my faith but with excitement, joy and certainty that God's Word will prove perfect and true 100% of the time no matter what lies this world serves up as truth.
Edited to add something I read just recently that may be of help to you.
Growing in faith - http://www.gotquestions.org/Christian-grow-faith.html
Last edited by treasures; June 21st, 2012 at 11:50 AM.
Reason: adding link
Do not store up for yourselves treasures on earth, where moth and rust destroy, and where thieves break in and steal. 20 But store up for yourselves treasures in heaven, where moth and rust do not destroy, and where thieves do not break in and steal. 21 For where your treasure is, there your heart will be also. ~ Matthew 6:19-21 ~