In the environment of the day, in a time when men had been debating the role of God in government for decades, in a nation whose founding document declared that rights were endowed by a Creator, in a convention stuffed full of Christians framing a document for a nation that was 95% Christian or more, such an enumeration would be unnecessary. It would be like beginning every sports page article sabout NASCAR with a detailed account of how the internal combustion engine works.
We live under the Constitituion of the United States. The Declaration is relevant in history, but is inapplicable to modern government.
The Declaration did not establish a government, it merely dissolved the bonds with our mother Monarchy. The Constitution makes no reference to God and THAT was intentional, good sir.