Many earnest people have cited that statement to prove that God's true church consists entirely of such faithful souls. But is that what Inspiration really teaches? The Bible does not describe the church of the last days as free from corruption, but actually in rather disgusting terms.
A backsliding church is just what Satan wants. The world looks on and gloats that the religion of the Bible doesn't make people any better than without it. And many of the faithful are tempted to turn away from the organized body as no longer being God's church. "By bringing into the church those who bear Christ’s name while they deny His character, the wicked one causes that God shall be dishonored, the work of salvation misrepresented, and souls imperiled." Christ's Object Lessons, p. 71.
Click on this link for a brief Bible study showing how Scripture depicts the church of the last days: The Condition of God's True Church Today
"Even in her best estate the church was not composed wholly of the true, pure, and sincere." The Story of Redemption, p. 323.
“How was it with the early church? Ananias and Sapphira joined themselves to the disciples. Simon Magus was baptized. Demas, who forsook Paul, had been counted a believer. Judas Iscariot was numbered with the apostles. The Redeemer does not want to lose one soul; His experience with Judas is recorded to show His long patience with perverse human nature; and He bids us bear with it as He has borne. He has said that false brethren will be found in the church till the close of time.” Christ's Object Lessons, p. 73.
"God has promised that where the shepherds are not true He will take charge of the flock Himself. . . . In the mighty sifting soon to take place we shall be better able to measure the strength of Israel. The signs reveal that the time is near when the Lord will manifest that His fan is in His hand, and He will thoroughly purge His floor." Testimonies for the Church, vol. 5, p. 80.