Contradictions
One might be tempted to think that skeptics are the most noble philosophers, unwilling to be swayed by mere dogma as they insist upon pragmatic, verifiable evidence. However, there is a fine line between skepticism and mere scoffing. A scoffer is one who pretends to be a skeptic but is really just too lazy to consider a matter intelligently or rationally. Most calling themselves skeptics would appear to be mere scoffers. Most will merely parrot... dogmatically, if you will, someone else's lists of things to be skeptical about.
Causes of apparent contradictions
Pile on the strawman: The scoffer builds a secondary claim for an apparent contradiction based on his first faulty claim.
Scope in time: Scoffers will compare events or circumstances at different times in history and force an apparent contradiction as if things can't change.
Translation: The lazy scoffer fails to understand the language scripture was written in, and base their scoffing on English translations.
Scope in text: Scoffers will fail to identify the boundaries of the text creating apparent contradictions.