25 Your bars shall be iron and brass.
As your days, so your strength will be.

Matthew Henry's Commentary on Deuteronomy 33:25

Commentary on Deuteronomy 33:24-25

(Read Deuteronomy 33:24-25)

All shall be sanctified to true believers; if their way be rough, their feet shall be shod with the preparation of the gospel of peace. As thy days, so shall thy strength be. The "day" is often in Scripture put for the events of the day; it is a promise that God would graciously and constantly support under trials and troubles, whatever they were. It is a promise sure to all the spiritual seed of Abraham. Have they work allotted? They shall have strength to do it. Have they burdens appointed? They shall have strength, and never be tempted above what they are able to bear.