There are various different evidences of true faith of saving faith, but here there is one in two parts set forward for our consideration. The first part is conscientiousness: a conscientious concern to please the Lord.
Do we practice self-examination? Those in mind in this passage do not like the idea of being challenged or encouraged to examine their hearts. They do not ask themselves, ‘What have I done today? How have I offended my God? How have I strayed from the mark? What should I have been doing that I have ignored and neglected?’ Do we examine ourselves privately before the Lord? And we become haughty people indifferent people. Daily self-examination is guaranteed to keep us humble and meek before the Lord, and sensitive to temptation so that we resist it.
This is not to be confused with a person who is a backslider. We distinguish between someone who is a false believer, and someone who is a backslider. It is possible, though it is a terrible thing, for any Christian to become a backslider. They may be a phase of rebellion in that person's life. This is not the same thing. The difference is that the backslidden Christian is never fully happy, is never really comfortable. The backslider may sin, may offend the Lord but not easily, not comfortably, conscience may from time be covered up and suppressed, or may not be functioning normally at all, and yet a backslider is not a happy living as an unbeliever, is not comfortable in the world and has constant spasms of anguish and shame, and even times of despair. Conscience although smothered and locked up, rather like John Bunyan's conscience in holy War, sometimes breaks free and roars and the backslidden person is troubled. Nor is this the same as the believer who has not gone wilfully into sin, but has stumbled and been overpowered maybe by a period of foolish neglect of prayer and daily reading of the word, and whose private devotions have been reduced to almost nothing. In a greatly weakened condition the believer has stumbled at some temptation and fallen, although never planning to do that. So we must distinguish between the person in Hebrews 10 and the true convert. Of course, we cannot readily tell these things – this message is to individuals to help them assess their own lives. We cannot go around saying, ‘I think that person is a backslider; I think that person is apostate altogether; I think that person is genuine’; these are so often hidden from us.