When I hear a fellow Christian say they believe something, I often will ask them why they believe it. It is surprising how many times either the person doesn't know why they believe it or isn't able to articulate why they believe it, or I get an answer like "That's what my Pastor says" or "That's what my family has always believed" or maybe "Isn't that what it says in the Bible?". I find that most of the time we can't give a credible answer to why we believe what we say we believe!
1Peter 3:15 tells us to "Always be prepared to give an answer to everyone who asks you to give the reason for the hope that you have." God is not simply calling on us to know the answers to a bunch of questions someone may ask. It is a call to a comprehensive defense of our hope or what we confess to believe. Not being able to defend a belief shows a lack of knowledge about that belief and anything we have such a lack of knowledge about should never be something we base our eternal hope upon. How can we have true faith in something that we have such little knowledge about that we can't explain why we believe it?
If you can't explain to someone else why you believe something, then you probably don't know enough about it to truly believe in it. Get into God's word and see if it holds up to scripture. Meditate on it and try to explain it to yourself in simple terms. Then you will be prepared to give an answer about, or defense of, your hope. People are looking for answers, not opinions.