Pro-life supporters are gathered in Washington this week for the annual March for Life. More than half a million people are expected to participate in the 41st annual march and most of them will be young people - better known as "millennials," writes Christy Stutzman. (AP Photo/Charles Dharapak)

In a few weeks, hundreds of thousands of people will join the March for Life in Washington, DC. What if there were three times that many praying?

January 22nd is the 43rd anniversary of the worst Supreme Court decision in our nation’s history. With Roe v. Wade, seven robed men gave America some of the most permissive abortion-on-demand laws in the world. Since that time, nearly 60 million unborn children have been killed in the womb.

This month, January, is the month so many American Christians memorialize the unborn through Sanctity of Life Sunday (this year on January 17), and the March for Life on the National Mall in Washington DC on January 22nd. And the day before the March, John Stonestreet and I will be speaking at two events: the Anglicans for Life conference and the Evangelicals for Life conference, co-hosted by Focus on the Family and the Ethics and Religious Liberty Commission. As you may know, John and I are very passionate about this issue. My wife runs a pregnancy care center here in New York City, and John’s mother ran one in Virginia.

Now, if you can join us in Washington DC, please do! But if you can’t, you can still be a part of the most significant cause of our day: the cause for life. How? Well, The Colson Center has prepared a free downloadable booklet called: 21 Days of Prayer for Life. We want to see millions of Christians appeal together to heaven to end this grave evil.

This full-color booklet was co-written by John Stonestreet and top pro-life apologist Scott Klusendorf, and is co-sponsored by the top pro-life groups in America: Students for Life, Focus on the Family, Save the Storks, the March for Life, Life Training Institute, CareNet, and others. The booklet will guide you through a three-week journey to pray for all of the victims of abortion: the unborn, expectant mothers and fathers in crisis, siblings, grandparents, and yes, even abortion clinic workers. It also includes prayers for pastors, as well as politicians and policy makers, an especially important group in this election year.

You see, Roe v. Wade, as bad of a decision as it was, did not “settle” the abortion debate in America. We are arguably, as a nation, more unsettled on this issue today than at any point since the decision was rendered. And there was serious momentum for the pro-life cause in 2015, especially with the Planned Parenthood expose videos. What better way for that momentum to continue in 2016 than to start the year with prayer?

But there’s something else powerful about this prayer guide. Each day features beautiful stories of life: of the dad who chose life for his son with Down syndrome, of the sibling who found peace for the loss of her aborted sister and forgiveness for her mom, of the student who courageously stood for life in a hostile college classroom. These stories will inspire you to also pick up the mantle and stand for life.

And as you pray, this guide will equip you to have pro-life conversations with your friends and neighbors. Did you know you can defend the dignity of unborn life through science and philosophy? Could you use some talking points of fetal development, and how to graciously answer the red herring arguments you often hear like: “don’t like abortion, well, don’t have one”? Then you need this prayer guide.

Eric Metaxas is the bestselling author of “Bonhoeffer: Pastor, Prophet, Martyr, Spy.” He is the radio host of “The Eric Metaxas Show” and the co-host of “BreakPoint.”