July 24. On this date in 1954, a letter written on behalf of Shoghi Effendi to the Spiritual Assembly of Japan stated that "So far as non-Bahá'ís affiliating with the Bahá'í Faith is concerned, either a person becomes a Bahá'í and accepts Bahá'u'lláh as the divine Manifestation for this day, or he does not."

July 24. On this date in 1954, a letter written on behalf of Shoghi Effendi to the Spiritual Assembly of Japan stated that "So far as non-Bahá'ís affiliating with the Bahá'í Faith is concerned, either a person becomes a Bahá'í and accepts Bahá'u'lláh as the divine Manifestation for this day, or he does not...they can only become Bahá'ís on the basis of accepting Bahá'u'lláh as a divine Manifestation, and of course, with this goes the acceptance of the Bab as the Forerunner, and Abdu'l-Bahá as the Center of the Covenant, and the present Administrative Order. When a person has reached the sea of immortality, it is idle to keep seeking elsewhere."

1384. Affiliation with Faith Alone is Insufficient
"So far as non-Bahá'ís affiliating with the Bahá'í Faith is concerned, either a person becomes a Bahá'í and accepts Bahá'u'lláh as the divine Manifestation for this day, or he does not. The tenets of the Bahá'í Faith are simple as outlined by the Guardian, but they do not permit of any variations. In other words, if any members of the ... Movement wish to become Bahá'ís, they will be most welcome; but they can only become Bahá'ís on the basis of accepting Bahá'u'lláh as a divine Manifestation, and of course, with this goes the acceptance of the Bab as the Forerunner, and Abdu'l-Bahá as the Center of the Covenant, and the present Administrative Order.
"When a person has reached the sea of immortality, it is idle to keep seeking elsewhere...."
(From a letter written on behalf of Shoghi Effendi to the Spiritual Assembly of Japan, July 24, 1953: Japan Will Turn Ablaze, pp. 76-77)

This statement seemingly contradicts 'Abdu’l-Bahá's previous statements. For example, on February 18, 1912, an "The Pittsburgh Pennsylvania Press" featured an article stating "In some respects the Bahá’í movement is the most remarkable of modern times. It isn’t a religion, in the sense that Christianity and Mohammedism and other faiths are religions. Its followers belong to many diverse sects, remaining Christian or Mohammedan or Brahmin as the case may be, and still being thorough going Bahis." During his visit to London in 1911, 'Abdu’l-Bahá had stated that "You can be a Bahá’í-Christian, a Bahá’í-Freemason, a Bahá’í-Jew, a Bahá’í-Muḥammadán."
During his visit to London in 1911, 'Abdu’l-Bahá had the following interaction with a Christian...

A student of the modern methods of the higher criticism asked ‘Abdu’l-Bahá if he would do well to continue in the church with which he had been associated all his life, and whose language was full of meaning to him. ‘Abdu’l-Bahá answered: “You must not dissociate yourself from it. Know this; the Kingdom of God is not in any Society; some seekers go through many Societies as a traveller goes through many cities till he reach his destination. If you belong to a Society already do not forsake your brothers. You can be a Bahá’í-Christian, a Bahá’í-Freemason, a Bahá’í-Jew, a Bahá’í-Muḥammadán. The number nine contains eight, and seven, and all the other numbers, and does not deny any of them. Do not distress or deny anyone by saying ‘He is not a Bahá’í!’