The question of the existence of a final cause or final causes is the subject of a philosophical school of thought known as teleology, dating back to the ancient Greeks. Teleological ideas suggest that natural processes are governed by a directive or purpose, i.e. the accomplishment of a particular objective - a final cause. Here we will explore the relationship between what Aristotle called efficient causes and final causes. We will look briefly at some relationships between efficient causes and final causes from classical mechanics, and we will also consider how arguments based on efficient causes and final causes have historically been formulated to develop two proofs for the existence of God. We will also consider what the nature of natural phenomena suggests about how God reveals himself in nature (natural revelation), and compare this to how God reveals himself in His word (special revelation).