In 2016, Donald Trump reintroduced the phrase “drain the swamp” into Washington-ese. He may have remembered how Ronald Reagan used the phrase in 1983 when he said he was in Washington to “drain the swamp.” However, the slogan predates these Republicans by a long shot. It was first introduced by American socialists Winfield Gaylord and Victor Berger as early as 1912.

Gaylord spoke metaphorically of draining the “capitalist swamp,” but he probably took the phrase from U.S. efforts to drain literal Panamanian swamps in the decades long project to build a canal. Hundreds, and perhaps thousands of workers had died from mosquito-borne diseases like malaria and yellow fever during the 33-year construction program.

Mr. Reagan resurrected the metaphor to signal his intent to root out corruption in Washington, D.C., and Donald Trump followed his lead. Though I am not any kind of expert on swamps, it doesn’t seem to me that Washington has become any less swampy. Though there are a lot of decent people working there, the infestation of greed and self-interest is as bad as ever.

The swamp problem is not just in Washington; it is much more provincial than that. It is so close as to be present in the human heart. This is how Jesus spoke of it: “For out of the heart come evil thoughts, murder, adultery, sexual immorality, theft, false witness, slander. These are what defile a person.”

The swamp in Washington will never be drained as long as we keep sending swamp creatures there. And we are all swamp creatures. That is the thing no one wants to admit.

Ours is the generation that discovered systemic evils and forgot about personal ones. But Jesus, on at least three occasions, spoke of people as evil. St. Paul acknowledged that “nothing good dwells in me, that is, in my flesh.” This is not to say that everything everyone does is evil. It is to say that everything everyone is has been tainted with evil. Under the right circumstances – say, in a position of power in Washington, D.C. – that evil can emerge and spread.

If draining the swamp must begin in individual’s hearts, and we cannot even admit that our hearts are swampy, there is no road forward. But what if we can admit that we have swampy hearts where some bad things hide? Can that swamp be drained?

“Drained” is perhaps not the right word. The Bible speaks of “cleansing” the heart. Indeed, God has designated the human heart a superfund site and has expended infinite resources to clean it up. He knows it is the only way the world will ever be set right.

Perhaps “cleansed” is more correct than “drained,” but how does that cleansing happen? It is more on the order of Hercules cleaning the Augean stables than Teddy Roosevelt draining the Panamanian swamps. In the fifth of Hercules twelve labors, he was required to clean the massive stables of King Augeas in one day. The king owned thousands of heads of livestock, which his herders drove into the stables each night—stables that were never cleaned.

Rather than grabbing a shovel, Hercules diverted two rivers, the Alpheus and Peneus, so that they were channeled right through the stables, washing away all the filth they contained. Hercules made the preparations, but the rushing water did the work.

Something analogous to this is required for the clean-up effort when it comes to people. We have our own role to play – as the biblical writers make abundantly clear – but the streams that do the work come from outside us. Those streams are faith, hope, and love. Whenever there is a confluence of those streams, people are changed, cleaned up, made new.

It is unrealistic to expect swamp creatures (like us) to drain the swamp. It goes against our nature. Before that can happen, we need, in the words of the old spiritual, “to be changed, changed from this creature, Lord, that I am.” That change cannot be initiated through political, technological, or organizational means. It is a spiritual problem which requires a spiritual solution.