Perichoresis refers to the mutual indwelling of the Father and the Son and the Spirit. The Father dwells in the Son, but at the same time, the Son dwells in the Father. The Father makes a home in the Son for Himself, but at the same time, the Son by the Spirit makes a home in the Father for Himself. Hilary of Poitiers described this as a mutual envelopment. The Father envelops the Son even as the Son envelops the Father. It doesn’t look like we’re getting very close to practical implications of the