Stephen Hawking, the renowned theoretical physicist, has said he believes humans will not survive another 1,000 years on this "fragile" earth, as the planet is at a growing risk being destroyed by a disaster, such as a sudden nuclear war, a genetically engineered virus, or the rising threat of artificial intelligence. In turn, evangelist Franklin Graham shared why Christians need not fear such a prediction.

Hawking, who has in the past said he is an atheist and declared "there is no God," made the ominous prediction during a speech delivered at the Oxford Union earlier this week.

"Although the chance of a disaster to planet Earth in a given year may be quite low, it adds up over time, and becomes a near certainty in the next 1,000 or 10,000 years," Hawking said in the speech, according to the Christian Science Monitor. "By that time we should have spread out into space, and to other stars, so a disaster on Earth would not mean the end of the human race."

He added that if humans want to survive, they should leave the earth and establish colonies on other planets.

The Mail Online points out that this isn't the first time the theoretical physicist has issued such a warning.

In January, during a  BBC Reith lecture, Hawking said humankind is inching closer to demise - as a disaster will inevitably strike the planet - and said we must leave Earth in order to survive.

"By that time we should have spread out into space, and to other stars, so a disaster on Earth would not mean the end of the human race," he said during the BBC lecture

Despite his depressing prediction, Hawking ended his speech on a positive note, according to British newspaper The Independent.

"Remember to look up at the stars and not down at your feet. Try to make sense of what you see, wonder about what makes the universe exist," he said. "Be curious. However difficult life may seem, there is always something you can do and succeed at. It matters that you don't just give up."

In a Facebook post shared on Thursday, evangelist Franklin Graham agreed that our time on earth is certainly limited, but encouraged Christians to remember that those who have put their faith in Jesus Christ can rest confidently in the hands of the Creator.

"He created this amazingly intricate universe we live in," he wrote.

The president of the Billy Graham Evangelistic Association also urged Christians to refrain from living in fear, but instead fix our eyes heavenward: "To me, you don't have to be a physicist to see the awesome power of the Master Creator when you see the innumerable stars and all of His vast creation," he wrote.

"We need to keep our eyes fixed on Him," he concluded, quoting Nehemiah 9:6, which reads,

"You alone are the LORD. You have made the heavens, the heaven of heavens with all their host, the earth and all that is on it, the seas and all that is in them. You give life to all of them and the heavenly host bows down before You."

Billy Graham's son has made his own predictions about the end of the world, stating in February that we are currently experiencing a "global epidemic of political and economic instability" which could signal the return of Christ.

"While the United States is focused on its own politics, the world is unraveling," he cautioned. "The danger signals are everywhere."

As the world is wallowing in "political and economic instability," it's not hard to realize that hope can only be found in Almighty God, Graham contended.

"It is imperative that we remember to pray for all 'those in authority' as God has commanded in His Word (1 Timothy 2:1-3)," he wrote. "One day He is going to wipe the slate clean and 'create new heavens and a new earth: and the former shall not be remembered, nor come into mind' (Isaiah 65:17)."

However, Graham ended with a note of encouragement for those who have placed their faith in God: "There is an eternal future with Him to look forward to," he wrote. "Jesus left us words of reassurance and hope, 'Let not your heart be troubled; you believe in God, believe also in Me...I go to prepare a place for you. And if I go and prepare a place for you, I will come again and receive you to Myself; that where I am, there you may be also' (John 14:1-3)."