Therefore, preparing your minds for action, and being sober-minded, set your hope fully on the grace that will be brought to you at the revelation of Jesus Christ. As obedient children, do not be conformed to the passions of your former ignorance, but as he who called you is holy, you also be holy in all your conduct, since it is written, 'You shall be holy, for I am holy.'"1 Peter 1:13-16
The logic is, to set one's hope on the grace of Jesus Christ is logically connected with preparing for action. This hope of future grace is also connected with not setting one's hope in the passions of past ignorance. That is, to have hope in Christ is not to have hope in worldly desires. Finally, this hope purposes to result in holiness according to the standard of God's holiness.
We see that hope for obedience is grounded in the hope of grace from Christ. Obedience consists of not being driven by worldly passion, but 'to be holy'. And our clue to what holiness is seems to be answered by the context: love for the brethren (1:22), putting away of malice, deceit, hypocrisy, envy, and slander (2:1). Furthermore, the oposite of holiness is again said to be "the passions of the flesh, which wage war against your soul." (2:11)
The point is holiness is primarily an internal war, and one that is won by setting one's hope on Jesus Christ. Future grace is all over the new testament...