Epiphanius Ancoratus 16

The Father, therefore, examines the chambers of the heart and knows the Holy Spirit searches the depths of God and He unveils the mysteries of God to the saints and teaches them in a way that magnifies God. This is to indicate we are not able to reach His understanding. This goes to show the Spirit is of God and is not foreign. There is nothing said about the angels or the archangels searching the depths of God. But of that day or hour no one knows, says the Son, not even the angels in heaven, nor the Son, but the Father alone (Mk. 13.32). You stupid fools, you so accustomed to not having the Holy Spirit so that when anyone is not in the Father they are not in the divinity of the Son. For just as the Father has life in Himself, even so He gave to the Son also to have life in Himself (Jn. 5.26) as well as, All things the Father has are mine (Jn. 16.15) says the very same holy Logos of God. What is of the Father but these things? The Father is of God and so also is the Son. Life is of the Father and so also is the Son. Light is of the Father, and quite plainly it is of the Son. Immortality is of the Father and also, in like manner, is of the Son. The Father is beyond comprehension and so it is of the Son. All things the Father is, so also is the Son. Therefore if the Father is of Him (the Son) then the ground of knowledge in the Father exists also in the Son and also exist in the Holy Spirit. If anyone is accustomed to the Son not knowing the day, let the ignorant one learn and not blaspheme. I have put forward the knowledge to him and now he knows. Tell me my beloved, (I call you beloved because I do not hate anyone, only the devil and all the works that he does and his treacherous beliefs.) I pray for you so that you might go back into God’s truth and not utterly destroy yourself with blasphemy against God. For the words of the holy God go deep and the Holy Spirit is ready to give it to you through the gifts of grace. For to one, it says, is given the word of wisdom (1Cor. 12.8) and to another a word of teaching, then it is followed by, But one and the same Spirit works all these things, distributing to each one individually just as He wills (2Cor 12.11) so that he might show you the Holy Spirit has absolute sway and authority. For the same Spirit gives all the gifts of grace as He so desires. Therefore, you must call to the Father so that He may unveil the Son to you. You must call to the Son so that He may unveil the Father to you. And you must call to the Father once again so that He might give you the Son and unveil the Holy Spirit and give Him to you so that He is in you. In this way, the Holy Spirit will unveil to you everything you need to know concerning the Father and Son and Holy Spirit so that you might learn there is not one gram of ignorance in the Son, not even in the Holy Spirit.