How do pre-trib rapture proponents interpret these verses being compatible with their theology?

John 17:15 >I pray NOT that thou shouldest take them out of this world, but that thou shouldest keep them from the evil. >Vs 20) Neither pray I for these alone, but for them also which shall believe on me through their word; This prayer followed Jesus' declaration in the previous chapter of this. John 16:33 >These things have I spoken unto you, that in me ye might have peace. In the world ye shall have tribulation: but be of good cheer; I have overcome the world. How do pretrib rapture proponents interpret and reconcil these verses being compatible with their eschatology?