Thomas Aquinas explains reason and faith in Chapter VII of Summa Contra Gentiles. Ha makes numerous connections to primary truths. He relates the first condition: the ability of the mind to know truth to reason, and he relates the first principle: assume there won't be contradiction, in connection to the Christian Faith. Thomas uses these two primary truths to prove faith and reason, and to defend them in their own subject area.
Christian faith exceeds the capacity of human reason. Thomas states that "those things which are naturally instilled in human reason cannot be opposed to this truth". Thomas makes a connection to the first condition. Beliefs that are instilled in humans cannot be contrasting to truth. What humans believe is naturally must be true, it is impossible to deem it false according to Thomas Aquinas. "Nor is it lawful to deem false that which is held by faith, since it is so evidently confirmed by God". Thomas makes two connections; he states that the human mind is unable to think it's false because God established that it was true. He also states that there can't be any contradiction because states that it's true.
"It is impossible for the aforesaid truth of faith to be contrary to those principles which reason knows naturally". Aquinas states that impossible for truth to have any contradiction because the principle states that there cannot be any contradiction in order to converse about truth. Objects and beliefs that are natural cannot have contradiction. Natural objects are unchangeable as long as it remains natural. Although some humans think there is confusion in reason, there cannot be any uncertainty in order for humans to discuss primary truths.
Thomas Aquinas connects both reason and faith through the two primary truths. He states that the divine Wisdom contains these principles, but whatever is contrary to the principles is contrary to divine Wisdom. "Therefore the divine Wisdom also contains these principles. Consequently whatever is contrary to these principles is contrary to the divine Wisdom; wherefore it cannot be God". The first principle of non-contradiction states that in order for humans to talk about truth people have understand no truth can be discussed unless there is the understanding of the primary truths. Thomas Aquinas discusses many relations that corresponds both faith and reason together. "Therefore God does not instill into man any opinion or belief contrary to natural knowledge". Aquinas believes that man has no contrasting opinion to natural knowledge, man's mind is pure. No contrary opinions will disprove that faith and reason cannot be discussed with different ideas.
Thomas Aquinas created this idea that people that believe in Christian faith believe in divine Wisdom, and divine Wisdom has no contradiction that it has to be true to be discussed with other people. He also says that Christian faith has no contradiction and must be true because it was created by God is pure and true, so the Christian faith cannot be contrasting. "Now contrary opinions cannot be in the same subject". If God had instilled conflicting knowledge in humans, then people's intellect would be obstructed from knowing truth. "Our intellect is stayed by contrary arguments, so that it cannot advance to the knowledge of truth".
Aquinas harmonized faith and reason together. He interrupted that knowledge cannot be contrasting because humans have opinions. God created us where humans would be able to contradict what he instilled in us from birth. Aquinas connected that God and the divine Wisdom have no contradiction in arguments because humans must first realize that in order to discuss faith the primary truths must be understood. Aquinas also believed that reason corresponded with the first principle, and faith corresponded with the first condition. Aquinas gave reasons that allow for there to not be any contrast in the Christian faith. He gives two examples, "Hence the apostle said, 'The word is nigh thee even in thy heart and in thy mouth. This is the word of faith which we preach'". Christian faith also has no contradiction and must be true because that is the way that God made humans, and the reason why the knowledge humans have cannot be obstructed in any way.
Aquinas gave thoughtful explanation to discussing how Christian faith, divine Wisdom and God must be true and have no contradiction. Humans cannot have conflicting knowledge otherwise "our intellect would not be able to grow. Aquinas makes the connection between faith and reason in Chapter VII more evident.