SORRY!
Dear friend you cannot get to heaven simply because you prayed a prayer once because the Bible says:
(Isaiah 1:15-18) And when ye spread forth your hands, I will hide mine eyes from you: yea, when ye make many prayers, I will not hear: your hands are full of blood. {16} Wash you, make you clean; put away the evil of your doings from before mine eyes; cease to do evil; {17} Learn to do well; seek judgment, relieve the oppressed, judge the fatherless, plead for the widow. {18} Come now, and let us reason together, saith the LORD: though your sins be as scarlet, they shall be as white as snow; though they be red like crimson, they shall be as wool.
(Luke 18:9-14) And he spake this parable unto certain which trusted in themselves that they were righteous, and despised others: {10} Two men went up into the temple to pray; the one a Pharisee, and the other a publican. {11} The Pharisee stood and prayed thus with himself, God, I thank thee, that I am not as other men are, extortioners, unjust, adulterers, or even as this publican. {12} I fast twice in the week, I give tithes of all that I possess. {13} And the publican, standing afar off, would not lift up so much as his eyes unto heaven, but smote upon his breast, saying, God be merciful to me a sinner. {14} I tell you, this man went down to his house justified rather than the other: for every one that exalteth himself shall be abased; and he that humbleth himself shall be exalted.
So you see my friend it is entirely possible to pray a prayer or even pray many prayers and not be saved. It depends on why you prayed, what you prayed and what you believed when you prayed.
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