Either Christianity is true or it's false. If you bet that it's true, and you believe in God and submit to Him, then if it IS true, you've gained God, heaven, and everything else. If it's false, you've lost nothing, but you've had a good life marked by peace and the illusion that ultimately everything makes sense. If you bet that Christianity is not true, and it's false, you've lost nothing. But if you bet that it's false, and it turns out to be true, you've lost everything and you get to spend eternity in hell.
Popular paraphrase of "Pascal's Wager"
If the views that some men hold are correct, it is plain we never ought to have had any Reformation at all. For the sake of peace, we ought to have gone on worshipping the Virgin, and bowing down to images and relics to this very day. Away with such trifling! There are times when controversy is not only a duty but also a benefit, and it is a plain Scriptural duty to "contend earnestly for the faith once delivered to the saints."
J.C. Ryle, Anglican Bishop who defended the gospel in valiant opposition to Rome
For grace pray much, for much thou needest grace;
If men thy work deride—what can they more?
Christ's weary foot thy path on earth doth trace;
If thorns wound thee, they pierced Him before;
Press on, look up, though clouds may gather round;
Thy place of service He makes hallowed ground.
John J. Penstone, from his poem "The Servant's Path"