Every person enlisting in the Pennsylvania Guard shall sign an enlistment contract and take and subscribe to the following oath of enlistment: "I do hereby acknowledge to have voluntarily enlisted this...... ..............., 19 , as a soldier in the Pennsylvania Guard for the period of the emergency plus six months unless sooner discharged by proper authority, and I do solemnly swear that I will bear true faith and allegiance to the United States of America and to the Commonwealth of Pennsylvania, and that I will serve them honestly and faithfully against all their enemies whomsoever, and that I will obey the order of the Governor of the Commonwealth of Pennsylvania and of the officers appointed over me according to law."