1. O Lord God, I see that patience is very necessary for me, for many things in this life do not happn as we would like.
I see well that whatever plans I make for my own peace, my life cannot be without some battle and sorrow....
2. If you say you are not able to to suffer so much, how then will you be able to suffer the fire of purgatory?
Of two evils we should always choose the lesser. Strive, then, on God's behalf to endure the little pains of this world, so that you may escape eternal torments in the world to come.
Leaving aside the issue of purgatory, Thomas is saying that it's far better to choose the "evil" of a hard struggle against sin in this life, rather than to suffer the evil of punishment for your sins in the next life.
Or, for us moms, facing the difficulty of training a toddler can be overwhelming at times, but how much better it is to face that struggle, that "evil," now rather than to put it off until the child is six or twelve or fifteen years old when disciplining him will require far more work and will yield scantier results.
That's very good counsel, and I wonder if The Imitation is the origin of that phrase. If so, its original meaning was nothing like the way it's used in modern politics.