People say that God is love and will never harm His children.  That is true.  But in the same way that a truly loving father will discipline his children, our loving God disciplines us (Revelation 3:19).  However unpleasant persecution may be, it is used by God to refine His people and strengthen those who want to trust Him more (James 1:2-4).  So, for the devoted believer, persecution enables faith to grow. The sad reality is that without problems, we would be inclined to live in our own strength and not by faith in the Lord.
 
Hebrews 12:4-13 explains this judgement/discipline process.  God is determined to get us right for heaven, and that we should be strong to witness to His grace until we get there.  Malachi 3:1-4 shows God’s resolve to purify His people even though the refining is painful.  Believing in Christ’s atoning sacrifice on the cross is the start of our salvation, but its purpose is that we shall be purified as well as redeemed (Titus 2:14).    

But if the pain of persecution is a sign of God's determination to purify His people, what about those who are determined to resist Him?  Peter says that Christians who endure persecution and purify themselves for God's holy service, are also living out a message from God.  That message is to the rest of the church, as their suffering shows the urgency to win the lost.  And it is a message to those who are disobedient: if God treats His own people in this way, what about those who refuse to submit to Jesus?
 
God's determination to "redeem us from all wickedness and to purify for himself a people that are his very own, eager to do what is good" (Titus 2:14), knows no bounds.  He has done everything necessary in Christ so that we may receive His grace.  Now, He continues to use even the hatred of the wicked for His purpose: sanctification for us and the announcement of judgement for the ungodly.  It is the Lord's desire, and should be ours, that sinners will turn and receive salvation so that they will not be overtaken by God's judgement (2 Peter 3:9).  Therefore, be strong to accept the Lord's discipline.  As you do so the church will be made bolder; and the demons will quake, knowing that sinners will see the grace of Christ in you, and will turn to receive His salvation.