MANILA (AFP) -- Cardinal Jaime Sin, the powerful spiritual leader of Roman Catholic Philippines, formally stepped down Friday with a plea to Filipino politicians to be more responsible in their jobs.

"Among all areas of Filipino life, it is politics that needs most the saving presence of Christ," he said at a solemn ceremony where he turned over his pastoral staff -- the symbol of his authority as archbishop of Manila -- to Vatican-nominated successor Gaudencio Rosales.

"Politics without Christ is the greatest scourge of our nation," said the 75-year-old Sin, his voice weak.

For nearly three decades, Sin wielded enormous influence in this Southeast nation of 80 million people, forcing the ouster of two corruption-tainted presidents -- the late dictator Ferdinand Marcos in 1986 and Joseph Estrada in 2001.

Marcos and Estrada were replaced by devout Catholics Corazon Aquino and incumbent Gloria Arroyo respectively, both of whom enjoyed the staunch support of Sin in Asia's bastion of Catholicism.

President Arroyo and Aquino as well other dignitaries on Friday joined more than 600 priests in witnessing the change of guard and welcoming Rosales, also a liberal who once campaigned strongly on environmental issues.

"The past 29 years have been difficult (filled with) rallies and peaceful revolutions, they were also years of greatness," the ailing Sin said. While he has was largely credited for transforming the Philippine church into a powerful political force, Sin said he had always been "a reluctant political archbishop." He asked the country to support Gaudencio, whom he said has "clarity of vision and piety of heart."