R. C. Sproul is a good Christian thinker. Along with John Piper and my own pastor Matt Chandler, Sproul is perhaps the top USAmerican reformed thinker and teacher.
But I'm not sure I agree with his article here. Basically he says that the charge from outsiders that the church is full of hypocrites is patently false. He does a great job of outlining where the word "hypocrite" actually comes from (ancient Greek acting term for wearing a mask). But he then states that Christians are sinners and that doesn't make them hypocrites so the outsiders are wrong.
Really, what makes Christians hypocrites is their hypocrisy, not their sinfulness.
Sproul is correct in a couple of ways. First, those outside the church will often use any excuse to avoid dealing with their own sinfulness, and pointing to Christian hypocrisy is one such way. We should not give them such easy outs. Second, probably the vast majority of believers are not hypocrites, just as Sproul says. However, too many well-known believers (and by "well-known" I'm not just referring to famous ones, but ones well-known in their own communities too) pretend that their sin is not as bad as those outside the church. They pretend that the sin they struggle with isn't really there, or doesn't really ever win.
This is what the world sees and calls hypocrisy, the hiding of our dirty laundry. So what are we to do? Shout our sins in public? Stand on the corner and confess our darkest lusts and fears? Probably not, although that might be better than sweeping it under the rug. But there should not be a hint of "betterness" in us. The whole "one beggar showing other beggars where he found something to eat" has much truth in it for us. We did nothing and have done nothing to impress God. Honesty with him, with ourselves, and even with the world is the best policy, even when it comes to our showing our sin. After all, where sin abounds, grace abounds even more. I've read that somewhere.