We are not to receive the words of those who come with a message that contradicts the special points of our faith. They gather together a mass of Scripture, and pile it as proof around their asserted theories. This has been done over and over again during the past fifty years. And while the Scriptures are God's word, and are to be respected, the application of them, if such application moves one pillar from the foundation that God has sustained these fifty years, is a great mistake. He who makes such an application knows not the wonderful demonstration of the Holy Spirit that gave power and force to the past messages that have come to the people of God. {1SM 161.2}
So because she is convinced of her own experience in the Advent movement, she cannot permit others to test the "pillars" even by bringing a "mass" of Scriptures.
The context of this quote is a controversy in Ellen White's time over the sanctuary doctrine. She notes that folks has already come to them for the past 50 years with scriptures that call into question the "pillars", but that folks are not to receive them.