God, Repentance of

Is the plan of God fixed, and are His purposes firm and sure, or are they subject to change in response to the disposition of things below?  In several places Scripture mentions God "repenting" of something:

• Gen 6.6, He repented of having created man.
• 1 Sam 15.11, He repented of having made Saul king.
• Jer 18.8 and 26.3,13, His intention to repent of the evil He had determined to inflict on His people as soon as He sensed any change of heart in them.

In several places Scripture documents God abrogating His decrees:

• Jonah 3.4, 10 God decreed destruction of Ninevah in 40 days, and then withheld that destruction in response to their repentance.
• Is 38.1,5; 2 Ki 20.1,5; 2 Chron 32.24  Through Isaiah God announced the impending death of King Hezekiah, but was then moved by the King's tears and prayers to defer it.

Consequently some assert, as Calvin put it, "that God has not determined the affairs of men by an eternal decree, but that, according to each man's deserts or according as He deems Him fair and just, He decrees this or that each year, each day, and each hour."  John Calvin, Institutes of the Christian Religion, Book 1, Chapter 17, Section 13, quoting Origen's De principiis III. i. 17.

Does the Scripture allow an understanding of God's "repentance" in a way similar to the conditions that cause/force a man to repent?  As Calvin put the question, "that either he is ignorant of what is going to happen, or cannot escape it, or hastily and rashly rushes into a decision of which he immediately has to repent?"  The question is readily answered by the explicit statement of Scripture to the contrary, in 1 Sam 15.29 (KJV), "And also the Strength of Israel will not lie nor repent (Hebrew nacham, to be sorry, regret, repent); for He is not a man that He should repent."  Historically previous to this event the principle was stated even by the pagan Balaam, "God is not like man that He should lie, nor as the son of man that He should change.  It cannot be that He will not do what He has said or not fulfill what He has spoken."  (Num 23.19)

What then does God mean when He inspired Scripture writers to describe Himself this way?  Simply this: like many other methods God uses to enable our finite minds to grasp aspects of God's infinite and essentially inscrutable nature and attributes, here God's purposes and actions are described in a way man can, at least partially grasp.  Calvin,

"What, therefore, does the word 'repentance' mean?  Surely its meaning is like that of all other modes of speaking that describe God for us in human terms.  For because our weakness does not attain to His exalted state, the description of Him that is given to us must be accommodated to our capacity so that we may understand it.  Now the mode of accommodation is for Him to represent Himself to us not as He is in Himself, but as He seems to us.  Although He is beyond all disturbance of mind, yet He testifies that He is angry toward sinners... So we ought not to understand anything else under the word 'repentance' than change of action, because men are wont by changing their action to testify that they are displeased with themselves.  Therefore, since every change among men is a correction of what displeases them, but that correction arises out of repentance, then by the word 'repentance' is meant the fact that God changes with respect to His actions.  Meanwhile neither God's plan or His will is reversed, nor His volition altered; but what He had from eternity foreseen, approved, and decreed, He pursues in uninterrupted tenor, however sudden the variation may appear in men's eyes."  (Calvin's Institutes, Book 1, Chap 17, Section 13.)