Uncertainty and doubt perplex and weaken immature Christians. Christ is to them an outside and distant person whom they endeavor with painful effort to bring near and to make real. They try to do the orthodox thing, to cherish certain beliefs about Him. But there is no warmth, no inspiration, no enthusiasm, no intense love. Their experience is much of the time dreary, and their Christian service is mechanical and constrained, not free, spontaneous and joyful.
What is lacking? Not the new birth, but a definite experience which follows regeneration. The new birth implants love divine. When this love has been tested and strengthened by obedience it is our privilege by faith to have a spiritual manifestation of Christ in our hearts. "He that hath my commandments and keepeth them, he it is that loveth me; and he that loveth me shall be loved of my father, and I will love him, and will manifest myself unto him."
In every generation since the day of Pentecost there have been witnesses to the fulfillment of this promise. They were never more numerous than they are to-day in all Christian lands and in all evangelical churches. They testify to a wonderful clearness of spiritual vision. Truth takes on reality and solidity. The eyes of the heart have been anointed as the recent application of the X-rays to fluorescent spectacles gives to the bodily eyes an amazing power of penetration called the fluorescent bath. Jesus is no longer a distant abstraction, but a person vividly near and real, the one altogether lovely. Love to Him now becomes intense, passionate and all-consuming. His commands are now delightful, and they are unhesitatingly obeyed. "When it pleased God," says Paul, "who called me by his grace, to reveal his Son in me, that I might preach him among the heathen (treated as dogs by the Jews); immediately I conferred not with flesh and blood." There in Damascus the scales of Jewish prejudice fell off from his eyes, and the Spirit gave them a fluorescent bath by which he could see Jesus, not now In the clouds above, but in his heart as an abiding guest. This explains his heroic career of labors, dangers and sufferings cheerfully undergone in attestation of the truth of Christianity.
— From The Gospel of the Comforter Chapter 18.