Regarding your questions, in the sense that they do not belong to disciplic succession, in that sense Christ, Buddha, and the others are not bona fide. But because they have got some special power we accept them as bona fide. Just like Buddha. We accept him as the Supreme Personality of Godhead. Sometimes they play like that because they may have to. Although they are bona fide, they play sometimes as unbona fide. For example, we reject Buddha as unbona fide, but we accept him as an incarnation of God. We worship Lord Siva as a Vaisnava, but as a demigod we reject him. But to speak the truth, these personalities are not bona fide because who is caring for them? This so-called resurgence of feeling for Christ by the young people is due to our Krishna Consciousness movement. They are seeing that the foreigners are here, there is some national feeling and they think why not our Christ? Whatever they are doing we do not approve. But that does not mean that they should stop their work, this factionalism will go on. But one can see by the results. It is better not to talk with these people. Better let them remain as Christians and Buddhists, we do not want to convert them. You tell them that if you stick to Christ you will come out all right. It is better to avoid these comparative studies.
From Srila Prabhupada's letter to Nityananda — Los Angeles 16 August, 1972