Isaiah 48:21
And they thirsted not when he led them through the deserts: he caused the waters to flow out of the rock for them: he clave the rock also, and the waters gushed out. And they thirsted not when he led them through the deserts: he caused the waters to flow out of the rock for them: he clave the rock also, and the waters gushed out.
The verse looks back to God's leading of Israel through the desert and through barren wilderness places, where He kept them from thirsting by bringing water from the rock for them. The supply was miraculous and met their need wherever they were, for He split the rock and caused the waters to gush out. Christ Himself led Israel, and the rock that went with them was Christ, the source of both their temporal blessings and their spiritual blessings.
That deliverance and provision show that the God who cared for ancient Israel is the Redeemer of His people and will provide for them. In its setting in chapters 48 through 52, the verse points to the work to be done at the present time. It calls for a united and determined effort without delay to proclaim the message throughout the world, including decided labor in the cities, an increase of workers to meet the demands of the work in the cities, and the bringing in of means to carry forward soul-saving.
It calls workers to put on the armor and to speak of the work, to pray over it and to believe in it, letting no voice hinder the work. It calls members who have means to remember their responsibility to help do this work without delay, reconsecrating themselves to be in harmony with God and with Christ His only begotten Son. They are to resist temptation to enter commercial enterprises instead of investing means in the Lord's work, and to study these chapters carefully while asking the Lord for willingness to do His bidding.