The word “systematic” refers to rightly ordering the themes and topics or doctrines we find in Scripture so that they reflect the material order of the reality of God and his works.
Therefore, systematic theology is the discipline of approaching God’s self-revelation systematically, identifying the teachings or doctrines in God’s revelation (God and the things of God), and describing their order and relationships.
Since theology includes the study of both God and the things of God, including faith and conduct, theology must be both theoretical and practical. Paul makes this abundantly clear in the letter to Titus. Doctrine accords with godliness (Titus 1:1). Titus must teach people to live a life which fits with sound doctrine (2:1). James tells us to be doers of the word and not just hearers (James 1:22-27), and Paul calls us to lead a life of worship by transforming our minds (Romans 12:1-2). Good systematic theology should reshape our minds and hearts and lead to godly living.