Jesus Christ is He Who came by water and blood, John says.  This is a verse difficult to interpret, but it seems best to explain the water and blood as referring to Christ’s baptism and to His propitiatory death.  As the second clause of the verse shows, this difficult passage is strongly connected to the witness of the Spirit.  We know that the Spirit of God came upon our Lord Jesus at the time of His baptism, and remained upon Him throughout the course of His earthly ministry, which was consummated by His sacrificial death upon the cross.  So, we might say that Christ “came,” or entered upon His earthly ministry, by the waters of baptism, at which time He was anointed with the Spirit and confirmed by the Father’s voice speaking from heaven.  But this was only the beginning of His work.  His mission was not complete until He fulfilled all the work the Father gave Him to do in earning salvation for His sheep.  This was accomplished by the outpouring of His blood, whereby atonement was made for our souls, and eternal redemption secured.  The Holy Spirit bore witness to the Messiahship of Christ throughout His ministry, by empowering Him to do the great works which the prophets foretold of Him.  And now the Holy Spirit continues to bear witness by working in and through Christ’s people, empowering them to preach the Gospel and to live holy lives, distinguished from the wickedness and impurity of this present evil world.  He is truth, and bears witness to the truth, as opposed to the lies with which Satan has enslaved the world.  Every one born of God hears the truth, believes the truth, and walks in the truth, because he is indwelt by the Spirit of truth.  To some degree, he will resemble his Master, Who was filled with the Spirit without measure.