From John Winthrop's historic shipboard sermon before the Massachusetts Bay colonists to President Reagan's second inaugural address, religion has had a strong influence on this nation, according to Prof. Robert N. Bellah of the University of California.

Speaking at a forum on religion and foreign policy at the Washington Cathedral, the sociologist best known for his work on civil religion warned against discarding the concept of America as a nation with a divine mission, despite disagreement as to how that mission should be carried out.

"The best that we have achieved as a people, a people that really has brought hope to millions all over the world, is tied up with our sense that we are a special people, that ours is a noble experiment upon which much depends, that we are, in Lincoln's words, 'the last best hope on earth,' " he said.

In addition to the place of religion as "part of our American culture . . . part of our national self-understanding," religious institutions have "always played a role in helping us think about our nation and its role abroad," he said.

Specifically, Bellah praised "American priests and nuns in Central America, who tell a different story from that which the administration wants us to hear" and who have "done us a great service in helping us keep our heads."

The churches have "provided a variety of public theologies that sometimes reinforce and sometimes criticize our civil religion, but which to some degree independently influence our domestic and foreign policies."

He cited the world missionary movement, beginning in the early 19th century, as one major influence. Despite shortcomings, "the missionary effort has deeply colored our whole attitude toward foreign policy," he said.

The missionaries' direct, people-to-people relationships "seemed the right way for America to relate to the rest of the world . . . . The missionaries were to be themselves exemplars of a freer, more self-confident way of living in their lives not only Christian charity but democratic freedom . . . .

"However much the reality belies the ideal, the conception that Americans in foreign lands, American policy toward foreign nations, should be helping others to help themselves is still a powerful element in our political culture," he said.

As a more recent example of the churches' direct impact on foreign policy, he said, is the growing concern for social responsibility, "reaching a kind of culmination in the two recent pastoral letters" of the American Catholic bishops.

The social responsibility expressed by the churches in the last 20 years adds "another dimension" to the individualism of the missionary movement, he said. "It perceives that the relations between nations are not only personal but structural, that economic and political considerations must be taken into account that transcend assistance to individuals."

While the missionary model taught us to "reach out to the neighbor in need," he said, "the social responsibility ideal teaches us that we will not be adequate to that task unless we also, as Christians, take responsibility for the structures and powers of our nation, correcting and reforming their injustices and abuses, so as to make our own society more exemplary and the world order more just."