Absolutely true.
"Suppose a nation in some distant region should take the Bible for their only law book, and every member should regulate his conduct by the precepts there exhibited! Every member would be obliged in conscience, to temperance, frugality, and industry; to justice, kindness, and charity towards his fellow men; and to piety, love, and reverence toward Almighty God ... What a Eutopia, what a Paradise would this region be." John Adams, February 22, 1756
"Our Constitution was made only for a moral and religious people. It is wholly inadequate to the government of any other." John Adams
"It is impossible to rightly govern the world without God and the Bible" George Washington
Read this one VERY carefully.
"Of all the dispositions and habits which lead to political prosperity, religion and morality are indispensable supports.... And let us with caution indulge the supposition that morality can be maintained without religion ... Reason and experience both forbid us to expect that national morality can prevail to the exclusion of religious principle." George Washington's Farewell Address
Furthermore, James Madison stated that the founding documents must always be considered in the correct context.
The error seems not sufficiently eradicated, that the operations of the mind, as well as the acts of the body, are subject to the coercion of the laws. But our rulers can have authority over such natural rights only as we have submitted to them. The rights of conscience we never submitted, we could not submit. We are answerable for them to our God. The legitimate powers of government extend to such acts only as are injurious to others. But it does me no injury for my neighbour to say there are twenty gods, or no god. It neither picks my pocket nor breaks my leg. If it be said, his testimony in a court of justice cannot be relied on, reject it then, and be the stigma on him. Constraint may make him worse by making him a hypocrite, but it will never make him a truer man. It may fix him obstinately in his errors, but will not cure them. Reason and free enquiry are the only effectual agents against error. Give a loose to them, they will support the true religion, by bringing every false one to their tribunal, to the test of their investigation. They are the natural enemies of error, and of error only. Had not the Roman government permitted free enquiry, Christianity could never have been introduced. Had not free enquiry been indulged, at the aera of the reformation, the corruptions of Christianity could not have been purged away. If it be restrained now, the present corruptions will be protected, and new ones encouraged. Was the government to prescribe to us our medicine and diet, our bodies would be in such keeping as our souls are now. Thus in France the emetic was once forbidden as a medicine, and the potatoe as an article of food. -Thomas Jefferson.
Funny how it says exactly what I'm saying in my posts above.