Tradition

Regarding the 159th verse of Surah Anaam (6), ‘On the day when some of the signs of your Lord shall come, its faith shall not profit a soul, which did not believe before, or earn good through its faith. Say: Wait; we too are waiting.’
Ali b. Rabaab narrates from Imam Sadiq (a.s.) who observed, ‘The signs allude to the Imams, while ‘some of the signs’ refer to Qaem, Muntazar. Then the one who has not affirmed Mahdi’s (a.t.f.s.) Imamat before his reappearance, will reap no benefit in doing so later, with the sword against his neck. This will be his fate, regardless of whether he has acknowledged the other Imams (before Mahdi (a.t.f.s.)).’
Yanaabi al-Mawaddah chap 71 pg 422