Nor has respondent Abalos proved by some evidence that the nature of his work on board a ship aggravated his illness.  No one knew when he boarded the vessel that he was sick of gallstone.  By the nature of this illness, it is highly probable that Abalos already had it when he boarded his assigned ship although it went undiagnosed because he had yet to experience its symptoms.   If respondent Abalos had instead been sick of asthma and the shipping company knew of it even as it assigned him to do work that exposed him to allergens, then it can be said that the company assigned him work that aggravated his illness.  Here, however, he himself was unaware that he had gallstone until excruciating pains manifested its presence for the first time when his vessel was sailing the seas.   The Court recognized in Vergara v. Hammonia Maritime Services, Inc. [19]  the significance of the adoption by the Department of Labor and Employment of the Philippine Overseas Employment Administration Standard Employment Contract as a condition for deploying Filipino seafarers working on foreign oceangoing vessels.  When the foreign shipping company signs that contract, there is assurance that it voluntarily subjects itself to Philippine laws and jurisdiction.  If the NLRC orders the payment of benefits not found in that contract, the particular seaman might be favored but the credibility of our standard employment contract will suffer.  Foreign shipping companies might regard it as non-binding to the detriment of other seamen.   ACCORDINGLY, the Court grants the petition, SETS ASIDE the decision of the Court of Appeals in CA-G.R. SP 95238 dated January 30, 2007 and its resolution dated March 19, 2007, and REINSTATES the decision of the National Labor Relations Commission in NLRC NCR CA 039306-04 dated February 23, 2006.          SO ORDERED.     ROBERTO A. ABAD