Someone wrote to me:
Another theological question: If the greatest commandments
are to love God with all your heart, and love your neighbour as
yourself, and bearing in mind that Jesus gives an example of this (Luke)
in the good Samaritan, immediately after making this statement - does
this mean that non-jews and non-Christians who love God with all their
hearts and their neighbour as themselves are obeying all the
commandments and will therefore also get eternal life?

You don't earn it by following the greatest or the least commandments. He's not waiting at the gate with a commandments checklist. It's not about that.

You get there by loving him and being loved by him. And that implies not rejecting him. John 3:16-18. Yes, of course, non-Jews who and non-Christians who are willing to love God and not refuse the gift he offers are welcomed in. That's the revolution that Christ brought to Judaism: relationship isn't limited to blood/family/tribal ties. They're welcomed in not because they have followed commandments but because they have loved and said yes to God and his way, Jesus. But in doing so, they are no longer non-Christians.

The question is a little like asking "how many keys does there need to be on a computer keyboard for it to be connected to the internet?" "It says to 'mouse-click here'; does that mean a trackpad won't do it, only a mouse?" No. The internet isn't really about that. It's about being able to send and receive signals and, once you can receive them, not turning signals away.

Jesus is being typically playfully paradoxical with the guy. Jesus says If you love me you'll keep my commandments. And what are his commandments? Essentially, that you love him.

Some of the guys that ask Jesus similar questions have a problem: they are trying to justify themselves. They are examining the wording to find out whether they can fit into the definition without changing. "Ah, but who IS my neighbour?" Jesus told the Good Samaritan parable not in order that the guy might jack up his commandment-compliance an extra notch, but so that he would change his attitude. Such people are in trouble not because there are commandments that they are violating, but because their attitude is not one of loving God, but of asking "how little can I get away with and still have it be called 'love'?" That, of course, is not a question love asks. Love asks, "What can I do to show you I love you?" not "How little can I do and still have you think I love you?"