Creator of all things, true source of light and wisdom, origin of all being, graciously let a ray of your light penetrate the darkness of my understanding.

Take from me the double darkness in which I have been born, an obscurity of sin and ignorance.

Give me a keen understanding, a retentive memory, and the ability to grasp things correctly and fundamentally.

Grant me the talent of being exact in my explanations and the ability to express myself with thoroughness and charm.

Point out the beginning, direct the progress, and help in the completion. I ask this through Jesus Christ our Lord.

Amen. 

Saint Thomas Aquinas, OP