By its inaction, the church in America can only blame itself for the nation's moral decline, said Pastor Rafael Cruz, father of Republican presidential candidate Sen. Ted Cruz.

Speaking to host Pat Robertson of "The 700 Club" Christian TV programme, Cruz said, "We are where we are primarily because the church has been silent."

"For too many years, the church has believed this lie of separation of church and state. That is neither in the Constitution nor in the Declaration," the ordained minister and traveling public speaker said, according to WND.

Cruz said now is "A Time for Action," which is incidentally the title of his recently published book. He believes Christian inaction in the face of societal change has been the church's greatest failing over the past 60 years.

He said this all started in 1962 when the church kept silent when the Supreme Court banned prayer from public schools in Engel v. Vitale.

The following year, the court banned organised Bible reading in public schools. Once again, church leaders failed to protest on the ground that they did not want to interfere in "political issues."

Cruz said this is wrong interpretation of the Constitution. "How can you call prayer a political issue? How can you call Bible study a political issue? But that's what the church did."

Again in 1973, when the Supreme Court upheld the right to abortion, the church kept silence, saying once again that abortion was a political issue.

Last year, the Supreme Court legalised same-sex marriage throughout the nation, saying all Americans now have this "constitutional right."

Cruz thinks that this time the church has finally woken up from its slumber and has finally realised that it can no longer stay silent about public policy issues that deal with morality.

Turning to this year's U.S. election, Cruz said he is saddened to see the Republican candidates slinging mud at each other instead of talking about the serious issues that face America.

One issue he considers critical is the appointment of a justice to replace Supreme Court Justice Antonin Scalia who suffered a sudden death last week. Cruz said the Senate should wait until the next president takes office before confirming a nominee.

If President Barack Obama is allowed to nominate Scalia's successor, Cruz said he fears the Supreme Court will take a "hard left turn" to the further detriment of the religious conservative sector.

"This could tilt the balance of the court, and ... this could be something that would affect America for the next 30 years," he told Robertson. "We don't have 30 years, Pat."