With this law, the General Assembly intended to keep servants and prevent slaves from fleeing.
Virginia had a rich economy based on tobacco. Slaves and servants made that economy possible and flourish. Servants signed contracts ( for almost 7 years some cases) and in return their masters provided them with food, clothing and lodging.
Even so, slaves sought comfort in running away as the working conditions were really harsh. Punishments were hard: the first time they were caught they had to double the time they were hired to. Second time, their masters could brand them in their skin.
But, after 10 years of this law, the burgesses admitted that it proved ineffectual as slaves and servants continue to run and escape.
Many years were going to pass by until servants' right started to be considered.