Worship: Addition Subtraction Deduction & Prudence

God's Word is sufficient for life and to regulate God's divine worship in His church. We are not to add to or subtract from Scripture. We are also bound to logical deductions from Scripture just as if those deductions were explicitly taught in Scripture. And we are to regulate the "circumstances" (i.e. a building, a pulpit, pews, air conditioning, time of service) of our worship by the light of nature and Christian prudence, while the "elements" (i.e. prayer, bible reading, preaching, singing, sacraments) are commanded and are always to be done.