Having just mentioned the end of the age, Jesus turns to the subject of persistent prayer. This might seem unrelated, but we are to pray for Jesus’s return all the time and trust that it will happen, even when it seems that evil men triumph in the world. To illustrate His point, He tells the story of a widow who asks for justice from a judge who doesn’t care about what God wants or how he should treat other people. At first, he refuses to grant her justice, but eventually he relents.
Because even an unrighteous judge does eventually do the right thing because a widow continues to bother him about it, then we can expect that God, who is perfectly just and righteous, will do right by those He has chosen. Because He is perfect, He will grant justice in His timing, not when we think we should get it. But even when He delays, we should keep asking for it in the expectation that He will give it to us. Evil may abound in the world, but justice and wrath are coming and will wipe it all away forever.
The last question Jesus poses in this section is meant to be meditative, rather than something we should try to answer in general. When He comes back, if He came today, would He find faith in your heart? Have you been seeking to speed His return? (See 2 Peter 3:11–12.) Have you been persistent and tenacious in studying His Word and following His commands, knowing for certain He will come back one day?
Put faith in our hearts that endures to the end.