It is entirely appropriate that a book dealing with the subject of Christian assurance should end with three final affirmations, introduced by the repetitive phrase “we know” in verses 18, 19 and 20. In some ways these statements are a summary of much of what John has been teaching. In another sense they are a reminder of how important affirmations are to Christianity.
Not everybody believes this, of course. In fact, some would even try to eliminate affirmations in the interests of a greater, though less meaningful, harmony among Christians. Erasmus of Rotterdam was one. At the beginning of the Reformation, Erasmus was a partial supporter of Martin Luther, whom he regarded as being right in many things. But Erasmus, the humanist, did not have Luther’s spiritual undergirding. Consequently, as the Reformation developed, Erasmus became increasingly distressed by thoughts of a rupture within Christendom and horrified at what he regarded as Luther’s excessive dogmatism.
At last, encouraged by friends, he wrote a book defending the freedom of the human will in spiritual matters and attacking Luther for his convictions. Luther might have admitted humbly that he could be wrong. He might have qualified his teaching in view of Erasmus’ attack. But Luther did neither. Instead he replied, in The Bondage of the Will, with an able defense of Christian certainty and with a reaffirmation of the Reformed position. Luther declared, “Nothing is more familiar or characteristic among Christians than assertion. Take away assertions, and you take away Christianity… Why then do you—you!—assert that you find no satisfaction in assertions and that you prefer an undogmatic temper to any other?“1
It is hard to doubt that the apostle John would have been quite pleased with Luther’s argument, had he been there to hear it. For John too believed in assertions and would have maintained that it is impossible to have Christianity without them. Moreover, just as assertions were important and necessary in John’s time and in Luther’s time, so are they important and necessary in our time.
We therefore properly conclude a study of John’s book with a study of these three certainties. We should know: 1) that the one born of God does not sin; 2) that we are of God; and 3) that the Son of God has come and has given us knowledge of the true God.
1Martin Luther, The Bondage of the Will, trans. J. I. Packer and O. R. Johnston (Westwood, NJ: Revell, 1957), 67.
