“Thy shoes shall be iron and brass; and as thy days, so shall thy strength be.” -Deuteronomy 33:25
Here are two things provided for the pilgrim: shoes and strength.
As for the shoes: they are very needful for traveling along rough ways and for trampling upon deadly foes. We shall not go barefoot — this would not be suitable for princes of the blood royal. Our shoes shall not be at all of the common sort, for they shall have soles of durable metal, which will not wear out even if the journey be long and difficult. We shall have protection proportionate to the necessities of the road and the battle. Wherefore let us march boldly on, fearing no harm even though we tread on serpents or set our foot upon the dragon himself.
As for the strength: it shall be continued as long as our days shall continue, and it shall be proportioned to the stress and burden of those days. The words are few, “as thy days thy strength,” but the meaning is full. This day we may look for trial, and for work which will require energy, but we may just as confidently look for equal strength. This word given to Asher is given to us also who have faith wherewith to appropriate it. Let us rise to the holy boldness which it is calculated to create within the believing heart.
[from Faith’s Checkbook by Charles H. Spurgeon]