What is Theology?

A short but sweet answer to the question, What is theology?, is found in the Aphorisms of Campegius Vitringa the Elder:

Theology is that doctrine (John vii.16, 17) by which man, though a sinner, is rightly instructed concerning God, His way, and His worship, to the attainments of sure consolation in this life, (Rom. xv.4,) and safety in the life to come. (John xx.31. 1 Pet. i.9, 10.)