Did Jesus not help a Gentile, a Roman Centurion who came to the Lord for help, "Lord he said, my servant lies at home paralyzed, suffering terribly" Jesus said unto him, shall I come and heal him? The Centurion replied, 'Lord I do not deserve to have you come under my roof, but just say the word and my servant will be healed, for I myself am a man under authority with soldiers under me, I tell this one go and he goes, and that one come and he comes, I say to my servant do this and he does it.
When Jesus heard this, he was amazed and said to those following him, "Truly I tell you I have not found anyone in Israel with such great faith, I say to you many will come from the East and the West and will take their places at the feast with Abraham, Issac and Jacob in the Kingdom of Heaven. But the subjects of the Kingdom will be thrown outside into the darkness, where there will be gnashing of teeth.
Then Jesus said to the Centurion, "Go! Let it be done just as you believed it would, and his servant was healed at that moment."
Is this not proof that Jesus knew the Gentiles who believed in him would already have been saved and become his heirs?