Kept by the Power of God through Faith !
Many who would pervert this text of scripture, attempt to make mans faith the cause of being kept, and so once a man looses faith, he is no longer kept ! What high handed mutiny against the Power of God !
Peter plainly sets forth that those born again are Kept by the Power of God through Faith, that is Faith is a product of the Power of God and it is being sustained by the Power of God. This is the same power by which one believes in the First place. The word power is the greek word dynamis and means:
strength power, ability
a) inherent power, power residing in a thing by virtue of its nature, or which a person or thing exerts and puts forth
b) power for performing miracles
c) moral power and excellence of soul
d) the power and influence which belong to riches and wealth
e) power and resources arising from numbers
f) power consisting in or resting upon armies, forces, hosts
Now we are speaking of Almighty God's Strength, Power and Ability here.
Now the same word Paul uses when saying that we believe according to the working of His Power,
Eph 1:19
19And what is the exceeding greatness
of his power to us-ward
who believe, according to the working of his mighty power,
So believing is a result of God's Strength being exerted, His Power. So the believer is kept a believer, no fear of apostasy, by the very Power of God.
Thats why it was written centuries before regarding the Blessings of the New Covenant
Jer 32:40
And I will make an everlasting covenant with them, that I will not turn away from them, to do them good; but I will put my fear in their hearts,
that they shall not depart from me.
You see that is what a believer is, a recipient of the New Covenant Blessings conferred upon them as a result of the Death of Christ.
That Power of God keeps the Believer in Faith. The preposition dia also means with or in !
So the phrase could read
1Pet 1:5
5Who are kept by the power of God in or with faith unto salvation ready to be revealed in the last time.
The believer is kept by the power of God in Faith !
God's Power keeps them in the Place of Faith or God's Power Keeps them with a supply of Faith.
The Point being, The cause of being kept through Faith is God's Power ! And the Faith is not the cause of being kept by God's Power as those who wrest God's word would tell us.