Story highlights Prayer and political rally was sixth stop on 50-state tour

Franklin Graham quotes his father Billy Graham saying nation must repent

Among those sins are abortion and same-sex marriage, which he called a great sin

Atlanta (CNN) Evangelist Franklin Graham on Wednesday urged thousands of Christians gathered near the Georgia Capitol to make their voices heard in this year's elections, saying the consequences of inaction are dire.

"I don't think we're going to make it another election cycle if we don't get God's voice back in the political arena," the reverend said after speaking to an estimated 4,500 people in Atlanta on a cold, blustery afternoon.

Graham has embarked on a 50-state "Decision America Tour." Atlanta was stop No. 6.

Georgia's Lt. Gov. told us this was the largest crowd they have had in Liberty Plaza--that's great! #DecisionAmerica pic.twitter.com/W9rjHyAV9v — Franklin Graham (@Franklin_Graham) February 10, 2016

"I want to get Christians to run for office at every level. The Christian voice needs to be heard," he said.

Graham's tour has a three-fold purpose: call the nation to prayer; remind people to vote part of a Christian and civic duty; and to have people look at the election year from a spiritual standpoint.

Read More