Man knows not himself as Satan knows him to tempt him where he is weakest. We all have an Achilles heel where the devil can shoot an arrow at to wound us critically. Hence at all times we must put on the whole armour of God so that there is not one solitary joint that is unprotected. Samson when he lost his hair, lost his eyes. We should tremble and know that we are as weak as water if God leaves us alone.

But Praise be unto God we have a well guaranteed Promise – “As thy days so shall thy strength be.” A Promise is nothing unless it can be fulfilled. The God who guides the stars in their courses, who directs the earth in its orbit, who feeds the burning furnace of the sun – He is the same God who has promised to supply us our strength in the day when we need it.

Notice the Promise is “as thy days” and not “as thy desires.” Ah, some have thought, if I had faith like so and so I think I should do wonders! That is why God does not let you have the faith because He does not want you to do wonders. That is reserved for God. Because you harbour vain glory in wishing for it.

The Promise does not say “as thy weeks” or “as thy months”. You are not going to have Monday’s Grace given to you on Sunday. You shall have Monday’s Grace given to you on Monday morning as soon as you rise. You shall have it day by day, no more than you want and no less. God’s people cannot be trusted with a week’s Grace all at once. They will spend it all by midweek and then indulge in pride and boasting for the amount of work they had done because of so much Grace given to them. And then they will fall.

Oh how sweet it is to think that we never need be afraid. If our troubles should become high as mountains, God’s Grace would become like Noah’s flood to cover the mountains. If God should send to you and to me a day such as there were none like it, He would send us strength such as there was none like it.

 The Promise is also expansive. “As thy days so shall thy strength be.” The strength given will expand according to how much you need for the day to face your troubles, your fears, your challenges, your mountains and your valleys. Hallelujah! Finally the Promise is long. “As thy days so shall they strength be.” It will be given you till you shall see your God face to face.

Inspired and extracted from Rev. Charles H Spurgeon’s sermon “As thy days so shall thy strength be.”(Deut 33:25) delivered on Sabbath morning 22 August 1858. www.archive.spurgeon.org