“God is spirit, and those who worship Him must worship in spirit and truth” (Jn 4:24). What is a “spirit?”
Christopher Stead of the Cambridge Divinity School explains how a statement that God is spirit would have been interpreted within ancient Judaism:
By saying that God is spiritual, we do not mean that he has no body … but rather that he is the source of a mysterious life-giving power and energy that animates the human body, and himself possesses this energy in the fullest measure. (Christopher Stead, Philosophy in Christian Antiquity (Cambridge: Cambridge University Press, 1994), 98)
Regarding John 4:24, Origen wrote:
I know that some will attempt to say that, even according to the declarations of our own Scriptures, God is a body, because . . . they find it said . . . in the Gospel according to John, that “God is a Spirit, and they who worship Him must worship Him in spirit and in truth.” . . . Spirit, according to them, [is] to be regarded as nothing else than a body. (Origen, De Principiis 1.1 (ANF 4:242)
Harvard Historian Harry Austryn Wolfson wrote:
in Scripture . . . there is no indication that by spirit and soul were meant any such principles as form or immateriality. (Wolfson, Philo, 2:95.)
The great Christian writer, Tertullian (ca. 200 A.D.) wrote,
For who will deny that God is a body, although ‘God is a Spirit?’ For Spirit has a bodily substance of its own kind, in its own form. Tertullian, “Against Praxeas,” in 7 Ante-Nicene Fathers, edited by Philip Schaff (Christian Literature Publishing Co., 1886)3:602
I hope this helps…