Genesis 2:17

Of the tree of the knowledge - thou shalt not eat - This is the first positive precept God gave to man; and it was given as a test of obedience, and a proof of his being in a dependent, probationary state. It was necessary that, while constituted lord of this lower world, he should know that he was only God's vicegerent, and must be accountable to him for the use of his mental and corporeal powers, and for the use he made of the different creatures put under his care. The man from whose mind the strong impression of this dependence and responsibility is erased, necessarily loses sight of his origin and end, and is capable of any species of wickedness. As God is sovereign, he has a right to give to his creatures what commands he thinks proper. An intelligent creature, without a law to regulate his conduct, is an absurdity; this would destroy at once the idea of his dependency and accountableness. Man must ever feel God as his sovereign, and act under his authority, which he cannot do unless he have a rule of conduct. This rule God gives: and it is no matter of what kind it is, as long as obedience to it is not beyond the powers of the creature who is to obey. God says: There is a certain fruit-bearing tree; thou shalt not eat of its fruit; but of all the other fruits, and they are all that are necessary, for thee, thou mayest freely, liberally eat. Had he not an absolute right to say so? And was not man bound to obey?

Thou shalt surely die - מות תמות moth tamuth; Literally, a death thou shalt die; or, dying thou shalt die. Thou shalt not only die spiritually, by losing the life of God, but from that moment thou shalt become mortal, and shalt continue in a dying state till thou die. This we find literally accomplished; every moment of man's life may be considered as an act of dying, till soul and body are separated. Other meanings have been given of this passage, but they are in general either fanciful or incorrect.

2:16-17 Thou shall die - That is, thou shalt lose all the happiness thou hast either in possession or prospect; and thou shalt become liable to death, and all the miseries that preface and attend it. This was threatened as the immediate consequence of sin. In the day thou eatest, thou shalt die - Not only thou shalt become mortal, but spiritual death and the forerunners of temporal death shall immediately seize thee.