The Greek noun assarion refers to a small Roman copper coin of minimal value — roughly 1/16 of a denarius (a day's wage). Jesus used this coin in His teaching on divine providence: 'Are not two sparrows sold for a penny?' (Matthew 10:29), and in Luke's version, five sparrows for two assaria (Luke 12:6).
Jesus deliberately chose the least valuable coin to make His point about the Father's care. The assarion was the minimum unit of market exchange — what you pay for something practically worthless. Yet not one sparrow sold for an assarion falls to the ground outside the Father's notice. The cheapness of the coin magnifies the preciousness of God's attention: if He attends to the most commercially insignificant creatures, how much more does He watch over those made in His image?