Summary: Some ways to identify if a person is an authentic Christian.
DETERMINING AN AUTHENTIC CHRISTIAN
INTRO: How do you determine an authentic Christian? Many people could profess to be believers, but they may only speak words. Jesus gave a means of determining the real Christian. Look at their lives to see if they are bearing fruit.
The predominant emphasis of John 15:1-11 (quickview)  is fruit bearing. Read the text carefully and notice the times Jesus mentioned fruit bearing (v. 6). Because of the importance Jesus gave to fruit bearing, we need to look at it carefully.
I. THE EXPECTATION FOR FRUIT (vv 1-3).
In the Old Testament, God’s people were compared to a vineyard (see Isa. 5). The owner of a vineyard expected grapes. Likewise, God expects fruit from His followers. The fruit of which Jesus spoke was the reproduction of the life of the Vine in the branches. Jesus looks for His life in the lives of His followers.
The fruitless (not bearing fruit), the vine dresser “takes away” or prunes away (Jesus is probably referring here to Judas). That it (the total vine) may bear more fruit. A good test for Christians and church members today.
Could the large number of inactive church members we have today be the results of God’s pruning so that the church would bear more fruit? Jesus pruned Judas from the group! Inactive church members are betraying Jesus just as Judas betrayed him.
II. THE CONDITIONS FOR FRUIT (vv. 4-6).
Jesus gave two conditions for fruit-bearing, pruning and abiding. Pruning means removing everything from a person’s life which would hinder growth (v. 2). Abiding means allowing Christ to live in a person. The term “abiding” describes the intimate relationship of the Vine with the branches or Christ with His followers.
The only way to continue “clean” (pruned) and to bear fruit is to maintain vital spiritual connection with Christ (the vine). Judas is gone and Satan will sift the rest of them like wheat.
There is nothing for a broken off branch to do but wither and die! Isn’t this what happens to those who forsake the church?
Notice that Jesus as the vine will fulfil his part of the relation as long as the branches keep in vital union with him.
III. THE BENEFITS FOR FRUIT (vv. 7-11).
Anyone knows that great benefits occur from fruitful vines. What happens when believers are fruit-bearing? First, others will know that a person is an authentic Christian because they can see Christ in his or her life. Second, the fruit brings glory to God (v. 8).
Verse 7 - This astounding command and promise is not without conditions and limitations. It involves such intimate union and harmony with Christ that nothing will be asked out of accord with the mind of Christ.
CONC: In walking through a fruit orchard, people determine the kind of tree by the fruit it has. When people walk through life and see you, can they see a Christlike life?