The following quote is from The Gospel of John, by Arno Clemens Gaebelein, page 183.
Those who heard Him speak and believed on Him when He was on earth received life, for He had said, "The hour is coming and now is, when the dead shall hear the voice of the Son of God, and they that hear shall live." It was true then, as it is true now, "He that heareth My words and believeth Him that sent Me hath everlasting life and shall not come into judgment, but is passed from death into life" (John 5:24). His disciples who had believed on Him possessed this life; they knew the Father and the Son, for "this is eternal life," as He tells us in His great prayer (chapter 17), "that they should know Thee the only true God, and Jesus Christ whom Thou has sent." But life abundant, the fullness of that life, the abundance of it, was made known after His finished work, after He had passed through death, was raised from among the dead, seated at the right hand of God, and after which the Holy Spirit came. Now the abundant life is fully revealed, and those who have believed on Him possess in Him that abundant life, which has triumphed over death; they are risen in Christ, seated in Christ, complete in Him, sons of God, heirs of God, indwelt by the Holy Spirit, one spirit with the Lord, identified with Him, and members of His body. This abundant life is the believer's portion. It does therefore not mean some kind of a deeper, individual experience, unscripturally termed "the second blessing," or "a holiness experience." Every believer through grace has this life abundantly.