History of the Ring Finger

Tertullian alludes to the ancient custom of wearing a gold ring on the fourth finger because it was believed that a vein ran from that finger directly to the heart. A woman was allowed to wear gold only there, in promise of marriage. In the medieval service the wedding ring was placed first on the thumb, "in the name of the Father," then on the index finger, "in the name of the Son," on the third finger, "in the name of the Holy Ghost' and on the fourth finger with the Amen.