Where in Scripture does it say we must accept The word of someone they are Christian? The Lord Jesus said by their fruits you shall know them, (Mt. 7:16,20) not by their words, for the kingdom of God is not in Word but in power. (1Cor. 4:20)
“They profess that they know God; but in works they deny him, being abominable, and disobedient, and unto every good work reprobate. “ (Titus 1:16)
Therefore, accept one another, just as Christ also accepted us to the glory of God.
Romans 15:7