Think with me for a moment about a dam that springs a leak. Before long what began as a tiny trickle grows to a rushing torrent, and the valley beyond the dam is submerged under water. Now, let’s say that you are the engineer who gets the call about repairing things. While the original problem was a small leak, the issue you are dealing with now is much larger. Not only do you have to repair the original leak, but you also have to repair the structural damage the leak caused as it widened. Not to mention you’ve got an entire valley to drain. The solution will have to be much larger than the original problem!
Something similar to our dam is taking place in Romans 5:12-18. In essence, Paul describes a problem and solution. The problem stems from Adam’s sin in the garden. With that one act sin and death were unleashed on the world. The solution comes with Christ’s act of obedience on the cross. With that one act, grace and life were extended to the same world. In the end Christ’s act is greater than Adam’s, because grace covers sin.
At the same time, we can’t just talk about Adam’s sin on its own. It is like that leak in the dam. Though it started small, it was joined by more and more sins until it became a torrent that flooded the world. As Paul puts it in 5:16:
Nor can the gift be compared with the result of one man’s sin: The judgment followed one sin and brought condemnation, but the gift followed many trespasses and brought justification.
When we talk about the cross, we’re talking about a torrent of mercy strong enough to cover the sin and guilt of the entire world! Among other things, that means that your sin is wholly and completely covered by grace. No matter the extent of the trespass, his mercy is more!