"Wherefore also we pray always for you, that our God would count you worthy of this calling, and fulfil all the good pleasure of his goodness, and the work of faith with power." (2 Thessalonians 1:11)
Believing faith should never be seen as the goal, only the beginning of wonderful growth in the "divine nature" (2 Peter 1:4-9).
Faith both preserves and protects us: Jesus boldly declared, "He that heareth my word, and believeth on him that sent me hath |present tense| everlasting life, and shall not come |future imperative| into condemnation; but is passed |pluperfect or past perfect tense| from death unto life" (John 5:24). "For the Lord preserveth the faithful" (Psalm 31:23). That’s pretty clear. Either those words are accurate or they are untrue. There is no middle ground.
Faith is the "shield" against the enemy: Many of us have read about the great "armour of God" described in Ephesians 6. Of the seven "pieces" listed in those verses, we are told, "Above all |take| the shield of faith, wherewith ye shall be able to quench all the fiery darts of the wicked." And when we "resist the devil" (James 4:7), we are to do so "in the faith" (1 Peter 5:9).
Faith gives us power for effective prayer: The "faith as a grain of mustard seed" promise in Matthew 17:20 refers not to size or amount, but to the quality. "If ye have faith as a grain of mustard seed … nothing shall be impossible unto you." We might translate that as, "If you have the same kind of faith as a mustard seed, nothing shall be impossible unto you." The "ask…seek…find" promise of Matthew 7:7 depends on our confidence in our heavenly Father. And finally, "this is the confidence that we have in him, that, if we ask any thing according to his will, he heareth us" (1 John 5:14). HMM III