Attemptng the Impossible

"God speed the year of jubilee
The wide world o'er!
When from their galling chains set free,
Th' oppress'd shall vilely bend the knee,
And wear the yoke of tyranny
Like brutes no more.
That year will come, and freedom's reign,
To man his plundered rights again
Restore.

God speed the day when human blood
Shall cease to flow!
In every clime be understood,
The claims of human brotherhood,
And each return for evil, good,
Not blow for blow;
That day will come all feuds to end,
And change into a faithful friend
Each foe.

God speed the hour, the glorious hour,
When none on earth
Shall exercise a lordly power,
Nor in a tyrant's presence cower;
But to all manhood's stature tower,
By equal birth!
That hour will come, to each, to all,
And from his Prison-house, to thrall
Go forth.

Until that year, day, hour, arrive,
With head, and heart, and hand I'll strive,
To break the rod, and rend the gyve,
The spoiler of his prey deprive --
So witness Heaven!
And never from my chosen post,
Whate'er the peril or the cost,
Be driven."

While reading Douglass for class, although the entire work was impressive, this piece at the end caught my attention the most. At least in my interpretation, He is talking about Christ's return, when all the evil and injustice in the world will come to an end. Tyranny, War, Slavery, and every evil that exists. He's longing for that day, hoping and praying for it to come soon. But, until that day, he's striving to fight against it all, whatever the peril or the cost, he realizes his duty and he's ready to lay his life down on the line to do what is right.
My question is this: What drives us? What keeps us at our post? What keeps us from surrendering under the everpresent pressures and struggles that we face day to day?
I wrote my paper on the posibility of a perfect society, and, as i had already believed and known for fact, the ideals that each of my sources and authors expressed as vital for that society, are not possible wthout perfect morality, which is not possible until the return of Christ. So we know that there is no way we can overthrow the evils of the world. Until Christ returns, the battle will never end, no matter how hard we push, no matter how many prayer meetings and community outreach programs we participate in. The world cannot be a perfect place on our own time.
So again i ask, what drives us? What drove Douglass to keep pushing on 'until that day.' Voltaire defines faith as 'believing things because they are impossible.' I know it to be impossile to change the world. I know it to be impossible to rid every corner of the planet of satan and his influences. In my mind i know that for fact. And yet, that same fact is what pushes me, as well as, i think, Douglass. I have a direct command from my God and Savior to be Jesus to the world. To stand up for what is just and holy, and to fight what isn't. And though it is impossible for me to change the world, i have faith that my God wouldn't tell me to do something that is a waste of time.