abc: 3)Why would anyone give up their faith after tasting heavenly things? If we are not supposed to throw our pearls to the swine and the dogs, why would God throw his to those who will trample on them later on?
I wouldn't apply this to God, we're all pretty much swine compared to Him! Why would someone give up their faith? Well...first I would say, one does not have to give up their faith to be lost. After all, even the devils had faith, right? So, it's more than just having faith or not having faith. Now, why would someone sin gravely after becoming a Christian? Because we're human and we have concupiscence, we are drawn towards sin. (The spirit is willing but the flesh is weak.) Also, look at Paul in Romans 7 around vs. 15...he is saved, right? But he still struggles with sin, saying "I do not do what I want, but I do the very things I hate." (I think we've all been there...caving into sin, caving into the temptation and feeling that shame, etc.) It's a nice idea that once we are Christians we won't want to sin anymore, and certainly our spirit is willing, but we are physical creatures too (sound familiar? lol) and our flesh is weak, which is exactly why we need Christ and the grace of God to keep us from sin. We're fooling ourselves if we think becoming a Christian means leaving behind all temptation.
abc: 4)the seeds that fall on the hard grnd and among thorns, both of them didnt produce any fruit. if fruit is how we deduce whether a person is saved or not, then y cant we say that they werent saved in the first place?
5)The seed does fall on all kinds of ground, but unless it sprouts, takes root and produces fruit can we say that they were saved?
Certainly there are people who never produce fruit and who were never saved, but that doesn't mean there aren't people who did produce fruit but fell away. Look at John 15:
Jn 15: 1: "I am the true vine, and my Father is the vinedresser.
2: Every branch of mine that bears no fruit, he takes away, and every branch that does bear fruit he prunes, that it may bear more fruit.
3: You are already made clean by the word which I have spoken to you.
4: Abide in me, and I in you. As the branch cannot bear fruit by itself, unless it abides in the vine, neither can you, unless you abide in me.
5: I am the vine, you are the branches. He who abides in me, and I in him, he it is that bears much fruit, for apart from me you can do nothing.
6: If a man does not abide in me, he is cast forth as a branch and withers; and the branches are gathered, thrown into the fire and burned.
7: If you abide in me, and my words abide in you, ask whatever you will, and it shall be done for you.
8: By this my Father is glorified, that you bear much fruit, and so prove to be my disciples.
9: As the Father has loved me, so have I loved you; abide in my love.
10: If you keep my commandments, you will abide in my love, just as I have kept my Father's commandments and abide in his love.
Look at all those conditional statements...If this, then that. If you bear fruit, then you will be pruned....if you don't, you will be cut off. Now, you can't be cut off unless you have already been part of the vine, so obviously that's not saying "You were never part of the vine," quite the opposite.
John 16:1 says, "I have said all this to you to keep you from falling away."
One can't fall away if he wasn't already part of something. Again, that contradicts the idea that if someone is sinful or not bearing fruit, that he was never truly a Christian, or never had faith to begin with. One CAN have faith, be a Christian, but fall away.
Another verse about being cut off/falling away, etc. Romans 11:
17If some of the branches have been broken off, and you, though a wild olive shoot, have been grafted in among the others and now share in the nourishing sap from the olive root, 18do not boast over those branches. If you do, consider this: You do not support the root, but the root supports you. 19You will say then, "Branches were broken off so that I could be grafted in." 20Granted. But they were broken off because of unbelief, and you stand by faith. Do not be arrogant, but be afraid. 21For if God did not spare the natural branches, he will not spare you either.
22Consider therefore the kindness and sternness of God: sternness to those who fell, but kindness to you, provided that you continue in his kindness. Otherwise, you also will be cut off. 23And if they do not persist in unbelief, they will be grafted in, for God is able to graft them in again. 24After all, if you were cut out of an olive tree that is wild by nature, and contrary to nature were grafted into a cultivated olive tree, how much more readily will these, the natural branches, be grafted into their own olive tree!
Right here, it says those who once were part of the tree by faith were broken off, and BE WARNED!!! Don't be arrogant, you too can be broken off, don't think you're immune! But even those who have been broken off can be added back again.
I don't know how much clearer it can be. And these are only a few examples of scripture, there are literally hundreds more. Actually, I've just listened to a great lesson about this, it's here.