He has studied those verses.
You didn't answer the question.
Take another stab at it and help me find an answer for the question asked, not change the subject.
Mat_4:1 Then was Jesus led up of the Spirit into the wilderness to be tempted of the devil.
Mat_12:18 Behold my servant, whom I have chosen; my beloved, in whom my soul is well pleased: I will put my spirit upon him, and he shall shew judgment to the Gentiles.
Mar_1:10 And straightway coming up out of the water, he saw the heavens opened, and the Spirit like a dove descending upon him:
Mar 1:12 And immediately the Spirit driveth him into the wilderness.
First Jesus and the Holy Spirit did exist here at the same time as is evidenced by the previous verses.
Second, what Jesus meant by it was necessary that He leave so the Spirit could come is not given clear explanation in scripture. For the modalist to assume that supports their doctrine is very weak. We do know that the HG was to come in to dignify the church age and the beginning of sharing the gospel to the gentiles and all the rest of the world. It is my position that this is what Jesus was referencing. But that in no way communicates that both Jesus and the HG could not be here at the same time.