Two physical objects cannot occupy the same space at the same time.
Understanding that the Father is the HolySpirit who is the SpiritOfChrist Jesus enables us to make sense of this statement.

Jesus is the image of the HolySpirit. There is one God who is spirit - the HolySpirit.

The day that Jesus is speaking of is the day of Pentecost when He poured out His HolySpirit into those who asked for Him.

When we are baptised with the HolySpirit -> we know that Jesus is in the HolySpirit -> that we are in Jesus -> that Jesus is in us.

If you have not been baptized with the HolySpirit you are missing spiritual revelation of Christ Jesus and are functioning without His presence and power in you.