The Practice of Piety consists --
First, In knowing the essence of God, and that in respect of, (I.) The diverse manner of being therein, which are three persons -- Father, Son, and Holy Ghost. (II.) The Attributes thereof; which are either Nominal or Real, -- (1.) Absolute, as, Simpleness, Infiniteness, -- (2.) Relative, as, Life, Understanding, Will, Power, Majesty.
Second, In knowing thy own self, in respect of thy state of Corruption and Renovation.
Third, In glorifying God aright, (I.) By thy life, in dedicating thyself devoutly to serve him, -- both privately, in thine own person; and publicly, with thy family, every day; and with the Church, on the Sabbath-day; -- and extraordinarily, by fasting and by feasting. (II.) By thy death, in dying in the Lord, and for the Lord.
Unless that a man doth truly know God, he neither can nor will worship him aright: for how can a man love him whom he knoweth not? and who will worship him whose help a man thinks he needeth not? and how shall a man seek remedy by grace, who never understood his misery by nature? Therefore, saith the Apostle, "He that cometh to God, must believe that God is, and that he is a rewarder of them that seek him," Heb. xi.6.
And forasmuch as there can be no true piety without the knowledge of God; nor any good practice without the knowledge of a man's own self; we will therefore lay down the knowledge of God's majesty, and man's misery, as the first and chiefest grounds of the Practice of Piety.