Of this a square plot of 500 by 500 cubits shall be for the sanctuary, with fifty cubits for an open space around it.
God sets apart land for His sanctuary first, before the tribes receive their shares, because what is given to support worship and religion sanctifies the whole; it is the first-fruits that make the lump holy. The priests' portion is fixed and measured so the sanctuary cannot devour the rest of the land, teaching us that giving for God's work and the ministry's support is an act of piety that brings perpetual blessing.
AI summary
Commenting on Ezekiel 45:1-8
Of this there shall be for the sanctuary,.... Or temple, the house before described in the preceding chapters: five hundred in length, and five hundred in breadth, square round about: that is, five hundred reeds square, as is manifest from Eze 42:16, and this denotes the largeness, perfection, and stability of the church of Christ, which the sanctuary was a type of: and fifty cubits...
Of this there shall be for the sanctuary - See the plan, A.