Into the Wardrobe

@AK: well said and aptly quoted.
@ postodave: not sure calvin's analysis works. God in His essence is unknowable, ie, among other meanings, not to be encountered, but remains Trinity, hence relations that are analogous to the ethical can be attributed. The Father is not the Son, etc; be as apophatic as you may, these relations can be the basis of valid conclusions.

P-dave: the difficulty is less than it looks. The Father is the arche/origin of the Trinity, from eternity: the Son is begotten [a label for an unknown mode, of which begetting is the closest analogy], the Spirit proceeds [a label for an even darker black box]. But in the temporal sequence [works, energies] the Son and the Father send the Spirit into the world. One clause is about being, the other about doing.

Further, known covers a range of relations. We can to a very limited extent know/ser/saber about God in His essence, primarily the content of the first statement above, but we can know/connaitre/conocer God in His energies/works, including His earthly life. 'Energies' is more like biography, activity, or deed, than it is like force, electricity, or water.