# teaching in their synagogues

"teaching in the synagogues of the Galileans" or "teaching in the synagogues of those people"

# preaching the gospel of the kingdom

"preaching the good news that God will show himself as king" 

# every kind of disease and sickness

The words "disease" and "sickness" are closely related but should be translated as two different words if possible. "Disease" is what causes a person to be sick. "Sickness" is the physical weakness or affliction that results from having a disease.