The orans (latin, prayer) gesture is an ancient mode of prayer common to many ancient religions. It is performed standing, elbows bent or at the side, with arms uplifted and palms upward- a gesture of supplication or pleading.
The orans position was widely used in early Christian prayer, but was gradually replaced by the submissive gesture in the laity, although it has been in continual use by priests of the Roman Catholic faith during the celebration of the Mass and other priestly offices. It has been in continual use by both clergy and laity in the Eastern Orthodox Church.
The gesture is also gaining new popularity in many charismatic evangelical churches, where it considered more joyful and uplifting.
A famous example of the Orant posture from the catacomb of Priscilla
From the funeral stele of an Egyptian Christian woman