"Chapter 18—“He Must Increase” This chapter is based on John 3:22-36 . For a time the Baptist's influence over the nation had been greater than that of its rulers, priests, or princes. If he had announced himself as the Messiah, and raised a revolt against Rome, priests and people would have flocked to his standard. Every consideration that appeals to the ambition of the world's conquerors Satan had stood ready to urge upon John the Baptist. But with the evidence before him of his power, he had steadfastly refused the splendid bribe. The attention which was fixed upon him he had directed to Another. DA 178"
"After these things came Jesus and his disciples into the land of Judea; and there he tarried with them, and baptized. And John also was baptizing in Ænon near to Salim, because there was much water there: and they came, and were baptized. For John was not yet cast into prison. Then there arose a question between some of John’s disciples and the Jews about purifying. And they came unto John, and said unto him, Rabbi, he that was with thee beyond Jordan, to whom thou barest witness, behold, the same baptizeth, and all men come to him. John answered and said, A man can receive nothing, except it be given him from heaven. Ye yourselves bear me witness, that I said, I am not the Christ, but that I am sent before him. He that hath the bride is the bridegroom: but the friend of the bridegroom, which standeth and heareth him, rejoiceth greatly because of the bridegroom’s voice: this my joy therefore is fulfilled. He must increase, but I must decrease. He that cometh from above is above all: he that is of the earth is earthly, and speaketh of the earth: he that cometh from heaven is above all. And what he hath seen and heard, that he testifieth; and no man receiveth his testimony. He that hath received his testimony hath set to his seal that God is true. For he whom God hath sent speaketh the words of God: for God giveth not the Spirit by measure unto him. The Father loveth the Son, and hath given all things into his hand. He that believeth on the Son hath everlasting life: and he that believeth not the Son shall not see life; but the wrath of God abideth on him."
Ellen White directly references John 3:22-36 in this passage.