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When George W. Bush moved into the White House in 2001, there was a letter waiting for him from Bill Clinton, and eight years later, he wrote his own missive to Barack Obama. Today, those notes were made public for the first time.

The letters were released by the National Archives and Records Administration, and include words of encouragement and reminders of the great responsibility that comes along with being president of the United States. Bush told Obama that there would be "trying moments. The critics will rage. Your 'friends' will disappoint you. But, you will have an Almighty God to comfort you, a family who loves you, and a country that is pulling for you, including me. No matter what comes, you will be inspired by the character and compassion of the people you now lead."

In his letter, Clinton told Bush that the "burdens you now shoulder are great but often exaggerated," and the "sheer joy of doing what you believe is right is inexpressible." He called Bush "fortunate" to lead the United States "in a time of profound and largely positive change, when old questions, not just about the role of government, but about the very nature of our nation, must be answered anew," and said his prayers were with Bush and his family.