Let’s discuss that interpretation, then.
Again, God's timing is exactly carried out, because at Pentecost (the prescribed time Jews had been practicing for generations) God's Spirit came upon the believers in Jerusalem and His Spirit has been with us even unto today, just as Jesus promised.
Scripture tells us that His Spirit will not always strive with men. Your salvation and mine depend upon the integrity of God, not the best I can do to obtain His Grace.
When He promised the comforter would come and would remain with men until a prescribed hour, Salvation was immediately based on His integrity not mine or yours.
When He promised His Spirit would remain with us until the last hour, He is great enough to have kept His promise right throughout the past 2000 years.
In this simple thing--that what Jesus promised that His Spirit would not depart from believers, that those who believe on Him cannot be snatched from His hand, is where Christinaity is at variance with the founding assertions of Mormonism.
Men may argue how He has kept His promise--the myriad of denominations and the apparent dichotomy of Catholicism and Protestanism evidence men's arguing over the 'hows'--but one ought not doubt that He is powerful enough to keep His promises.
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You asked regarding my assertion that the thief did precisely what God requires for Salvation, “Please, walk me through that verse so I can understand better why you see it that way.
John 6: 28 - 40
Then said they unto him, What shall we do, that we might work the works of God?
Jesus answered and said unto them, This is the work of God, that ye believe on him whom he hath sent.
They said therefore unto him, What sign shewest thou then, that we may see, and believe thee? what dost thou work?
Our fathers did eat manna in the desert; as it is written,He gave them bread from heaven to eat.
Then Jesus said unto them, Verily, verily, I say unto you, Moses gave you not that bread from heaven; but my Father giveth you the true bread from heaven. For the bread of God is he which cometh down from heaven, and giveth life unto the world.
Then said they unto him, Lord, evermore give us this bread.
And Jesus said unto them, I am the bread of life: he that cometh to me shall never hunger; and he that believeth on me shall never thirst.
But I said unto you, That ye also have seen me, and believe not. All that the Father giveth me shall come to me; and him that cometh to me I will in no wise cast out. For I came down from heaven, not to do mine own will, but the will of him that sent me. And this is the Father's will which hath sent me, that of all which he hath given me I should lose nothing, but should raise it up again at the last day. And this is the will of him that sent me, that every one which seeth the Son, and believeth on him, may have everlasting life: and I will raise him up at the last day.
In that short passage we hear Jesus explain what is the work God requires for Salvation--Jesus uses the metaphor of the manna from Heaven to signify the source of life He brings to men.
In that passage we also read the promise that those believing on Him will have this everlasting life. Jesus does not add baptism or temple ordinances or sanctified underwear or multiple wives ‘and so on‘ …
And lest a Mormon apologist try to read the passage ‘everyone that seeth the Son’ in too strict a way, Jesus in many other passages spoke of ‘eyes to see and ears to hear’ when referring to the gift of spiritual sight and spiritual hearing.