What does Jesus demand of his followers in order for them to be recognised as true disciples? A brief look at the Sermon on the Mount can help us find out.
First, a true disciple will have the character defined in the Beatitudes. The list of features includes humility, sorrow for sin and its effects, gentleness, purity of heart, love of mercy, and a desire for peace. If we have these aspects in our character, we are true disciples.
Second, a true disciple will take seriously the matter of his indwelling sin. In a series of references to the ten commandments, Jesus takes his listeners through several situations in which he stressed the necessity of inner conformity to the law of God. He said that it was not enough to refrain from actual murder – instead he stated that hateful thoughts and spiteful words would kill the person’s own soul. He said that it was not enough to refrain from physical immorality – instead he stated that lustful thoughts were as dangerous as physical sin. He said that the command to love one’s neighbour extended far beyond one’s acquaintances – instead the concept of neighbour included loving one’s enemies and doing them good. He even said that to engage in acts of revenge (an eye for an eye) was a sign that the person was on the road to a collapse. But the point he was making is that all these wrong attitudes and actions arise from a failure to deal with indwelling sin. Jesus also stated that dealing with such sins would be difficult and painful; he likened it to cutting off a limb or removing an eye. Yet it is better to have limited pain than a wholesale collapse.
Third, a true disciple will engage in regular spiritual activities and Jesus mentions three in particular: giving to the poor, prayer and self-denial (fasting). The first is a practical evidence of concern for those in need and it is such a basic evidence of true Christianity that it is stressed throughout the Bible. A person that does not have compassion on the needy is not a true disciple of Jesus Christ. Of course, it is hard to imagine why a person who never gives to the physical needy should expect to receive anything from God to meet his spiritual needs.
Prayer is also performed in obedience to Jesus Christ and it is clear from his teaching on it that he regarded prayer in general to be a straightforward activity of a disciple. Prayer for Jesus was the drawing near of children to the heavenly Father, an activity of delight and expectation. He taught his disciples to speak to the Father about the beauty of his perfections, about the progress of his kingdom, and the provision of their own needs.
I am not sure if fasting alone is recommended by the reference to it or whether it is as an example of doing without activities that give pleasure in order to pursue more important goals. Fasting was not to be continuous, otherwise the person engaged in it would not be here for long. I suspect that Jesus may be using it as an example of assessing our priorities, of testing our willingness to make personal sacrifices in order to obtain for ourselves and for others greater spiritual blessings. Fasting without prayer is of no value in a spiritual sense, and similarly sacrifices of time and possessions are of no value unless accompanied by prayer and seeking for God.
Fourth, a true disciple will live primarily for heaven and secondarily for earth. Jesus highlights this distinction by referring to how his disciples react to possessions. He does not mean that his followers should not have any, but he does stress that material things should not distract them away from their priorities. Instead he points out that possessions, as with everything else in life, are under the providential control of God and the understanding of this great reality will enable his followers to have the proper attitude of trust in God regarding these matters. Their priority in life should be living for heaven day by day. This attitude will give to each true disciple an eternal perspective on all the things of time.
This brief survey of the Sermon on the Mount enables us to identify four basic principles of true discipleship. So how should we respond to this searching requirement of Jesus? First, his words demand that we become realistic regarding the spiritual life. We are called to a life of spiritual discipleship. It is not enough to have an external list of practices that will satisfy onlookers; our souls are under the eye of the One who can penetrate to the depths of our hearts.
Second, we must repent of our failings. The fact of the matter is that no disciple is perfect. We can see this is the case from the original disciples that Jesus had, including the twelve apostles. A very important distinguishing mark between the true and the false among them was the issue of repentance. The obvious example of a contrast is Peter and Judas – Peter repented and continued as a disciple; Judas did not and his life ended in calamity. Repentance should not be a reluctant activity of a true disciple. On the contrary, he should enter God’s presence to confess sin with an expectant heart, one that is sorry for sinful failures but which also anticipates receiving divine forgiveness. Therefore, repentance should be a habitual attitude of a true disciple.
Third, we must continually resolve to walk in the path of inner obedience. This should be our aim each day. And we can have this resolve because we know that the Holy Spirit will continue to enable his people to move on the life of holiness, desiring to be more and more obedient to the Saviour’s words.