"Or do I make my plans in a worldly manner so that in the same breath I say, 'Yes, yes' and 'No, no'?" (2 Corinthians 1:17)
The majority of what I hear from Christians mouth about salvation is "Yes, yes" and "No, no".
They speak of God's Grace (Jesus Christ) and turn right around and preach works. "Believe and obey". God does His part and you do yours, right?
Wait a minute. I thought you just said it was by grace? "I did". But you said I have to do something. "Yes. You have to obey". Then you've just added works to grace! You're stumbling over the stumbling stone because you simply cannot accept the Grace of God! You explain it in theory but deny it by practice! You say two different things in the same breath! Do I have to work for it or don't I? And if I must work, then what must I do!? What standard of obedience must I live up to? What exactly must I do to be obedient?
Or the more subtle approach most people take is that they really hammer the fact of "If you believe, then you will do good works". If thats true, then why stress it so much? If good works are natural result, then why are you so worried about it?