Saint Diadochos of Photiki: We Must Make Ourselves a Dwelling-place for the Holy Spirit

Only the Holy Spirit can purify the intellect, for unless a greater power comes and overthrows the despoiler, what he has taken captive will never be set free ( cf. Luke 11:21-22).
In every way, therefore, and especially through peace of soul, we must make ourselves a dwelling-place for the Holy Spirit.