Here's a list of quotes that I liked about the Atonement. You can find more quotes about other topics like family, agency, obedience, and more.
1) “The fundamental principles of our religion (are) the testimony of the apostles and the prophets concerning Jesus Christ, … that he died, was buried, and rose again the third day, and ascended up into heaven; and all other things are only appendages to these which pertain to our religion.” (Smith, Joseph. Elder’s Journal. July 1838)
2) . “Under the Father’s great eternal plan, it is the Savior who suffered. It is the Savior who broke the bands of death. It is the Savior who paid the price for our sins and transgressions and blots them out on condition of our repentance. It is the Savior who delivers us from physical and spiritual death… The Savior’s atoning sacrifice…is best understood and appreciated when we expressly and clearly connect it to Him.” (Nelson, Russell M. “Drawing the Power of Jesus Christ into Our Lives.” General Conference. April 2017.)
3) “Jesus was the only one who could offer such an infinite atonement, since He was born of a mortal mother and an immortal Father. Because of that unique birthright, Jesus was an infinite Being.” (Nelson, Russell M. “The Atonement.” General Conference. October 1996)
4) “The Creation required the Fall. The Fall required the Atonement. The Atonement enabled the purpose of the Creation to be accomplished. Eternal life, made possible by the Atonement, is the supreme purpose of the Creation. To phrase that statement in its negative form, if families were not sealed in holy temples, the whole earth would be utterly wasted.” (Nelson, Russell M. “The Atonement.” General Conference. October 1996)
5) “The Savior has admonished us to become as He is. Thus, following the Lord includes emulating Him. We continue to come to know the Lord as we seek through the power of His Atonement to become like Him. In His mortal ministry, Jesus marked the path, led the way, and set the perfect example.” (Bednar, David A. “If Ye Had Known Me.” General Conference. October 2016.)
6) “The Atonement of Jesus Christ provides the cleanser necessary to be made pure and clean, the soothing salve to heal spiritual wounds and remove guilt, and the protection that enables us to be faithful in times both good and bad.” (Bednar, David A. “Come and See It.” General Conference. October 2014.)
7) “Because of the Atonement of Jesus Christ, all spirits blessed by birth will ultimately be resurrected, spirit and body reunited, and inherit kingdoms of glory that are superior to our existence here on earth.” (Cook, Quentin L. “Our Father’s Plan—Big Enough for All His Children.” General Conference. April 2009.)
8) “Overcoming the world is not one defining moment in a lifetime, but a lifetime of moments that define an eternity…Praying, repenting, following the Savior, and receiving His grace lead us to better understand why we are here and who we are to become.” (Anderson, Neil L. “Overcoming the World.” General Conference. April 2017.)
9) “The miracle of the Atonement can make up for imperfections in our performance.” (Stevenson, Gary A. “Your Four Minutes.” General Conference. April 2014.)
10) “You have the Savior of the world on your side. If you seek His help and follow His directions, how can you fail?” (Stevenson, Gary A. “Your Four Minutes.” General Conference. April 2014.)
11) “The Atonement, which can reclaim each one of us, bears no scars. That means that no matter what we have done or where we have been or how something happened, if we truly repent (the Savior) has promised that He would atone. And when He atoned, that settled that… The Atonement can wash clean every stain no matter how difficult or how long or how many times repeated.” (Packer, Boyd K. “The Plan of Happiness.” Ensign. May 2015.)
12) “The miracle of the Atonement can make up for imperfections in our performance.” (Stevenson, Gary A. “Your Four Minutes.” General Conference. April 2014.)
Aside from quotes, I have a position statement/ testimony for each of the eight topics that I talk about in the project. Lastly, I have a personal application project about the Atonement.
Feel free to read up!