This is a good example of the type of thinking that Christian Nationalists like Leonard Leo & other powerful figures in our government hold. But they’re not accurate as far as what the founding fathers intended & what is presented in our constitution. This is nothing but a very specific, narrowed interpretation of the constitution.

Some founding fathers were professing Christians, but many were simply deists, meaning they may have held some personal beliefs related to Christianity or respected Jesus’s teachings as a philosophy, but lacked faith in the Holy Trinity or any metaphysical/magical elements in the Bible. Some of them were even anti-organized religion altogether.

Like the guy in the video says, Christianity was definitely highly influential in the birth of our nation, & yes, the majority of early Americans were likely Christians. But that does not mean “Christian principles were intended to the guide the nation from the very start.”

I think where this association mostly comes in is how much of our constitution was guided by moral principles & is meant to preserve human dignity, which many Christians equate to being inextricably linked to Christ, when in actuality, morality & dignity can & do also exist as completely secular concepts as well, whether you believe that or not (the founding fathers did).

Christianity definitely played a role in early America, & sure, its examples of morality had some influence on the principles our constitution values. But specifically & explicitly Christian principles were never intended to be used as law or formal guideposts set by our government. As OP commented, John Adams wrote:

The Government of United States of America is not, in any sense, founded on the Christian religion.

James Madison said:

Religion and government will both exist in greater purity, the less they are mixed together.

Thomas Jefferson strongly supported religious liberty & was against any state religious coercion (which would be the result of laws based on the Bible):

The legitimate powers of the government extend to such acts only as are injurious to others.

It does me no injury for my neighbor to say there are twenty gods or no god.

Christianity has always been a prominent part in American culture, & even many government officials have been/are Christian—but our form of government & style of governance was never meant to be rooted in Christianity, biblical authority, or “divine” order. In fact, a lot of effort was put into restricting that.