Shas spiritual leader Rabbi Ovadia Yosef on Thursday urged US President George W. Bush to free imprisoned Israeli spy Jonathan Pollard. In a letter to the US president, Yosef wrote: "One of the most important mitzvot in Judaism is redeeming captives. At this opportune time, I offer my humble request on behalf of the Jews of Zion that Your Excellency release our brother, the prisoner Jonathan Pollard, who is serving a sentence for spying on behalf of the State of Israel. His health is deteriorating." "Please answer my request affirmatively and you will be blessed from the heavens," continued the letter. "The creator of the world who has accompanied you in your struggle to achieve world peace will grant you mercy and grace for many days and years of long life."