There is no other saving gospel
Scripture uses farmers terms. It calls true believers “wheat”, and fake believers “tares”. A tare is a plant that grows up with wheat, but is not true wheat.
Tares are like the piglet that suckles with the kitten’s mother cat. The piglet thinks he’s a kitten because he likes the milk. But he’s only a pig, not a cat. The same is true of folk who like the idea of being blessed by Christ, but never yield to Him.