Matthew 6:19-34
The single eye is that which has only one object in view. That object, this "treasure", for the believer, is Christ. In the Scriptures it is said we behold Him "with open face" and that vision lightens up the whole of our inward being (read 2 Corinthians 3:18; 2 Corinthians 4:6-7). Our heart cannot be at one and the same time in heaven and on the earth. To cherish heavenly treasure and at the same time be laying up treasure for ourselves down here are two things which are completely incompatible. It is just as impossible to serve more than one master (v. 24). Otherwise the orders received will often be contradictory. But in renouncing mammon (that means riches; see Luke 16:13), are we not going to expose ourselves to privation, and run the risk of being short of what we need for the present time? The Lord anticipates this lack of faith. "Therefore I say unto you, Take no thought for your life . . ." (v. 25). Let us open our eyes wide, as the Lord bids us. Observe in creation the innumerable small signs of the tender care and goodness of the heavenly Father: the flowers, the birds . . . (cf. Psalms 147:9).
God will never be debtor to those who put His interests before their own, to those who have chosen Him (Luke 10:42). But that is where we must start.