● 1Cor 16:22 . . If anyone love not The Lord, let him be accursed.
One's love of The Lord is evidenced by loyalty.
● John 14:15 . . If you love me, you will comply with what I command.
● John 14:21 . .Whoever has my commands and obeys them, he is the one who loves me.
● John 14:23-24 . . If anyone loves me, he will obey my teaching . . He who does not love me will not obey my teaching.
Does a Muslim have to be a terrorist to be accursed? No; they only have to be a loyal follower of Muhammad ibn `Abdullāh instead of a loyal follower of Jesus Christ; same goes for Atheists, Nonreligious, Baha'i, Buddhists, Chinese Universalists, Confucianists, Jains, Kabbalah mystics, Shintoists, Spiritists, Taoists, Zoroastrians, Jews, Sikhs, and Hindus-- they're all accursed and there is nothing to be gained in arguing about it.
How many people am I talking about? Well, as of mid 2014, worldwide there were:
8,200,000 Jehovah's Witnesses
451,292,000 Chinese Folk Religionists
The grand total of just those categories alone is 5,369,071,000
If those figures are in the ball park, and if classical Christianity is the reality; then a minimum of at least 75% of the earth's 2014 population of 7.2 billion people didn't love The Lord.
NOTE: Jehovah's Witnesses and Mormons are Christians, yes, but not in the classical sense.
Joseph Smith's movement is a spin-off; in other words: there's some classical Christianity in Mormonism, but comprises only a portion of Mormonism. The rest of it is extreme, to say the least.
Neither do Jehovah's Witnesses qualify as Christians in the classical sense. Charles Taze Russell's movement is a spin-off too. There's some classical Christianity in the Watchtower Society's doctrines, but comprises only a portion of Russell's doctrines; and his slant on it is very peculiar.
BTW: An informative book that I personally consider an essential volume in every Christian's library is called: "Kingdom Of The Cults" by Walter Martin.