זוהר בראשית — דף רלג ע”א

When Israel comes to be buried in the Land of Israel, each one ascends above. The dead buried outside the Land of Israel will roll underground until they reach the Land of Israel. Belief in the resurrection of the dead is one of the foundations of faith. Whoever does not believe in resurrection is not a son of the World to Come. Burial in the Land of Israel is a unique privilege for the elevation of the soul.