Many will come with Jesus' name saying Jesus exists as Christ. Exists is the key word.
http://biblehub.com/greek/1510.htm
accompanied* (1), accompany* (2), am (138), amount (1), amounts (1), appear* (1), asserted* (1), become* (5), been (45), been* (1), being (26), belong (3), belonged* (1), belonging (1), belonging* (1), belongs (4), bring* (1), came (1), come (5), consist (1), crave* (1), depends* (1), do (1), done* (1), exist (3), existed (4), existed* (1), falls (1), found (1), had (8), happen (4), have (2), have come (1), lived (1), mean (1), mean* (2), means (7), meant (2), originate (1), owns (1), remain (3), remained (1), rest (1), sided (1), stayed (2), themselves (1), there (6), turn (1).
Are you able to see a future tense there? If you can, can you please show me?