It is a wooden sword made of Khadira tree. The Apa.1-15-13 mentions-sphya samya prasitraharanamiti khadiran/-the sphya, samya and the prasitraharana should be made out of Khadira wood. It is placed in the northern side of the Garhapatya fire. It is the first of the ten Sacrificial weapons. It is mentioned in the Texts - sphyasca kapalani ca agnihotrahavani ca surpam ca krsnajinam ca samya ca ulukhalam ca musalam ca drusacca upala ca etani vai dasayajnayudhani-the Sphya (the wooden sword), the Kapala-s (pot-shreds), agnihotrahavani (the ladle used in agnihotra), Shurpa (the winnowing basket), Krishnajinam (the skin of black antelope), Samya (the Yoke-pin), Ulukhala (the mortar), Musala (the pestle), Drushad and Upala (the lower and the upper grinding stones)-these are the ten yajnayudha-s or Sacrificial Weapons. Sphya is the first among them. In the Pindapitryajna (the sacrifice of lump offering to the Manes), a line is drawn with the Sphya, and on it the pindapradana is done. In the construction of Vedi (altar), it is used for levelling the ground, digging, touching the paridhis, drawing line for placing the ajyasthali etc. The Agnidhra, holding the Sphya, tied with the strings used for binding the Sacrificial fuel called idhma around it, standing at the place specified to him, does the pratyasravana With the utterance of astu srausat. The Apa.2-15-4 states astu srausadityagnidhropa renotkaram daksina mukhastisthan sphyam sammargascadhara-yan pratyasravayati. At the time of a Soma sacrifice the Agnidhra does as above standing in the Agnidhra hut - agnidhre some Apa.2-15-5. sarvatraivamasruta pratyasrute bhavata 2-15-6 - in all the cases the call for asravayana by the Adhvaryu and the responds astu srausat by the Agnidhra happen in this way. The Sphya is also employed in the Stambayajurharana. In the construction of Uttaravedi, lines are drawn with the Sphya. At time of purchasing Soma, it is optionally employed for gosaptama padollekhana. In the Somayaga known as Sadyaskra, the Sphya or a post with Sphya at the top is used optionally. The Apa. 22-3-7 mentions - sphyo yupah sphyagro va - the Sphya or a post with Sphya at the top should be used as the sacrificial post.
In the antyesti, it is placed in the right hand of the Sacrificer.