Fellowship with the Father, who can be truly known as Father only in this self-revelation through the Son, is here represented as effected through the medium of fellowship with the Son. And since in this fellowship is grounded that eternal divine life, in which alone true blessedness and joy can be found; John represents it as the object of his whole preaching, as likewise of this Letter (intended to revive in their hearts the contents of that preaching, in opposition to all the corruptions and impurities of which we have spoken) to promote that joy: "And these things write we unto you that your joy may be full." All impurities and corruptions of the christian's inward and outward life, must also introduce disturbance into the joy or blessedness grounded in the divine fellowship of life with Christ. In this pastoral Letter, designed to avert such a danger, what he seeks is this: that their joy may be full, that in fellowship with Christ they may find their full joy.