This is what the "Pay Attention Book" unit 5 p93 said [ I guess it is still current}
This differs from what apparently has been said about simply holding other beliefs being apostacy, and of course it differs greatly from 2 John 7 - 11 where it applies only to one who denies the Christ Jesus
Apostasy.
Apostasy is a standing away from, a falling away, defec-
tion, rebellion, abandonment; it involves teaching false
doctrines, supporting or promoting false religion and its
holidays or interfaith activities. (Deut. 13:13, 15; Josh.
22:22, ftn.; Acts 21:21, ftn.; 2 Cor. 6:14, 15, 17, 18;
2. John 7, 9, 10; Rev. 18:4)
Those with sincere doubts should be helped, dealt with
mercifully. (Jude 22, 23; w82 9/1 pp. 20-1;w80 8/1
pp. 21-2)
Apostasy includes action taken against true worship of
Jehovah or his established order among his dedicated
people. (Jer. 17:13; 23:15; 28:15, 16; 2 Thess. 2:9, 10)
Persons who deliberately spread (stubbornly hold to and
speak about) teachings contrary to Bible truth as taught
by Jehovah's Witnesses are apostates.
If it is learned that a person has taken up association with
another religious organization, the matter should be inves-
tigated, and if verified, a committee should be formed.
If it is clearly established that the person has joined
another religion and intends to remain with it, the
94
"Pay Attention to Yourselves and to All the Flock"
elders would make a brief announcement to the congre-
gation that such- one has disassociated himself. (w86
10/15 p. 31 )
Working secularly for a false religious organization could
put one in a position similar to that of one preaching false
doctrine. (2 Cor. 6:14-16)
Celebrating a false religious holiday would be similar to
performing any other act of false worship. (Jer. 7:16-19)