Lincoln was sometimes criticized during political elections in his career because he never joined a church.  He was accused of being an Atheist.  Apparently, he rejected to some degree his parents’ Baptist heritage.  But as he grew older and rose in the political ranks, he seemed to talk about spiritual things more.  He began attending Presbyterian churches and even had one of his children baptized.  One interesting testimony is given from one pastor who asked him if he loved Jesus.  His response was the following:

When I left Springfield I asked the people to pray for me.  I was not a Christian.  When I buried my son, the severest trial of my life, I was not a Christian.  But when I went to Gettysburg and saw the graves of thousands of our soldiers, I then and there consecrated myself to Christ.  Yes, I love Jesus.

Source:  A Patriot’s History of the United States by Larry Schweikart and Michael Allen.  Their sources for this statement are documented in note 137 on page 857.