Reveling in the subjunctive, Jewish sages of old have said that all is
ordained by God except the reverence and love of God.  In this way they
recognized that God has granted man space to make choices.  Without
violating that which makes us human, namely, our freedom to choose,
God executes his Covenant.  Thus, when a certain individual asked Jesus:
"What must I do to inherit eternal life?" he received in reply two
questions: "What is written in the Torah?" and "How readest thou?"
(Luke 10:25- 26), the implication being that the answer to the inquirer's
question is found, not only in the written word according to the normal
signification of words, but within himself as the interpreter of those
words.

     The promises of the Covenant are not a guaranteed outcome but a
guaranteed opportunity to apprehend and apply God's Law.  Is there no
place then within the Covenant for certitude? In God, yes; in ourselves,
no.  There's no place for saying: "once-in-grace-always-in-grace-no-
matter-how-much-a-disgrace."

     Examples of conditionality:

If my people, which are called by my name shall, humble
themselves, and pray, and seek my face, and turn from
their wicked ways; then will I hear from heaven, and will
forgive their sin, and will heal their land.      (II Chronicles 7:14)

If that nation, against whom I have pronounced, turn from
their evil, I will repent of the evil that I thought to do unto
them.  And at what instant I shall speak concerning a nation,
and concerning a kingdom, to build and to plant it; if it do evil
in my sight, that it obey not my voice, then I will repent of the
good, wherewith I said I would benefit them.  (Jeremiah 18:7-10)

   Jesus also employed the "if" word.  To his community of believers in Sardis,
he said:

If therefore thou shalt not watch, [then] I will come on thee
as a thief, and thou shalt not know that hour I will come
upon thee.                                                                      (Revelation 3:3)

     As well did the apostle Peter used the if word:    

For if these things [faith, virtue, knowledge, godliness, brotherly
kindness, charity] be in you and abound, [then] that make you
that ye shall neither be barren nor unfruitful in the knowledge
of our Lord Jesus Christ.                                                      (I Peter 1:8)