Thy shoes shall be iron and brass: this may note either,
1. Their great strength, by which they should be able to tread down and crush their enemies, as Christ's feet for this very reason are said to be of brass, Revelation 1:15. Or,
2. The mines of iron and copper, which were in their portion, whence Sidon their neighbour was famous among the heathens for its plenty of brass and iron, and Sarepta is thought to have its name from the brass and iron, which were melted there in great quantity. Compare Deuteronomy 8:9. Or,
3. The strength of its situation; and so some ancients and modems render the words, thy habitation or thy enclosure shall be iron and brass, i.e. fortified as it were with walls and gates of iron and brass, being defended by the sea on one side, by their brethren on other sides, as also by mountains and rivers. So shall thy strength be, i.e. thy strength shall not be diminished with thine age, but thou shalt have the rigour of youth even in thine old age; thy tribe shall grow stronger and stronger.