What does it look like when heaven is being torn open? Mark 1:10 says, “As Jesus was coming up out of the water, he saw heaven being torn open and the Spirit descending on him like a dove.”
Maybe Jesus had a vision into the heavenly abode of God and saw the turmoil rendered by the departing of the Holy Spirit, commissioning Jesus for his servant role on earth. But I tend to think that Jesus saw something physical. What could Jesus physically see? Maybe this refers to the closest heaven, which is visible, that is the atmosphere.
Imagine with me what we would see if the atmosphere were ripped open. What we normally see is blue and cloud. The atmosphere gathers light and bounces it around, making the haze of color that lights our days, even when the sun is blocked from view. If that atmosphere of oxygen, ozone, water molecules and dust were ripped open, what would we see? We would see the black of space through a separating curtain of blue and cloud.
Maybe the Holy Spirit’s visible presence (in the form of a dove) was so powerful, that all of nature must shrink back from him to allow his passage.