God
- After the Reformation, people had a new found faith and respects for the church. Europeans wanted to spread Christianity to other parts of the world, including the teachings of the Gospel. Religion was a means of control. The more people controlled by a religion, the more power that religion had, and thus the more chance of dominance. Europeans believed they could save souls through Christian salvation. They also believed it was their duty to spread the word of God.
Gold
- In general, wealth was a driving motivation of European exploration. The Ottoman Turks had taken control of the eastern Mediterranean and Europeans wanted to find a new route to Asia for trading. The rise in new monarchs led to the competition for wealth through trade and conquering new lands. Upper class men, especially in Spain, had limited power and wanted to seek their fortune elsewhere (Americas especially). Individual explorers, such as Christopher Columbus (although he wanted to spread religion as well) wanted profit and recognition to their name. The spice market was also a huge profit of trading and several countries tried to gain control of spice trade.
Glory
- Somewhat mentioned in "gold," individuals and countries wanted recognition to their name. Prestige was a driving force for exploration. The more land and money a country owned, the better their chance of domination in Europe.
Here are 2 sources.
https://answers.yahoo.com/question/index?qid=20080927092935AAtI4Cr
https://sites.google.com/site/almasexplorationproject/the-three-g-s