To “stand in the gap” means to expose yourself for the protection of another, to make defense against an immediate danger, to take the place of a fallen defender. It is a common principle in God’s word to us, the Bible.
In Ezekiel 22:30 (NIV), God says to His prophet Ezekiel:
I looked for someone among them who would build up the wall and stand before me in the gap on behalf of the land so I would not have to destroy it, but I found no one.
God looked for a righteous man from His people to stand with Him against their bad behavior.
In Psalm 106 (The Message), the scene is recounted when Moses came down from the mountain with the 10 commandments. The people had grown impatient waiting on Moses and had begun worshiping the man-made golden calf.
Fed up, God decided to get rid of them — and except for Moses, his chosen, he would have. But Moses stood in the gap and deflected God’s anger, prevented it from destroying them utterly.
This time Moses stands in the gap. Moses was only a man, however. He could not seal the gap, only block it for a time.
Jesus, the Son of Man, came to stand in the gap between God and man once and for all. Through his sacrificial death and resurrection, our fractured relationship with the Father was forever healed. The gap is sealed; the wall is complete. Hallelujah!