John 4:24 does say that God is a spirit. But let’s not assume that he is only a spirit. 1 John 4:8 says God is love and we all love that aspect of God. Deuteronomy 4:24 also says that God is a consuming fire. That’s because he is an awesome God. So awesome that when he was on Mount Sinai the Israelites were sure they were going to die from the sound of his voice but when Elijah was at the same mountain God spoke to him in a still small voice. But still the same God.
Therefore its no wonder that he is both LOVE and a CONSUMING FIRE even at the same time and all in righteousness. This is why he is a spirit. We must use other verses to help us understand the physical nature of God. Spirit is not a description of physical resistance in any form. The GOD of the Bible is awesome and he does have a voice.