While salvation can be lost, (Hebrews 10), it is gained in baptism (Bible on baptism, I Peter chapter 3 verse 21 http://www.newadvent.org/bible/1pe003.htm#21), not in water alone but though obedience,
Yet, while baptism cleanses, it can be forgotten,
worse, still is the punishment of those who abandon this faith- into mortal offense:
"20 For if, flying from the pollutions of the world, through the knowledge of our Lord and Saviour Jesus Christ, they be again entangled in them and overcome: their latter state is become unto them worse than the former. 21 For it had been better for them not to have known the way of justice than, after they have known it, to turn back from that holy commandment which was delivered to them. 22 For, that of the true proverb has happened to them: The dog is returned to his vomit; and: The sow that was washed to her wallowing in the mire."
And this offense causes the sinner's prayers for sanctification without confession, or those of brothers- not to be answered (I John chapter 5 v 13-16), nor shall those who pray out of sin be answered (James chapter 4 verse 3 http://www.newadvent.org/bible/jam004.htm#3).
Yet there is the promise to the Apostles (John 20 verse 23 http://www.newadvent.org/bible/joh020.htm#23), and those to succeed them (Acts chapter 1 verses 25, 26), that through our admitting the truth, for every sin is against reason, and God himself is essence, and their using their power, we may gain forgiveness via the sacrament.
From Good News Bible,
1 There is no condemnation now for those who live in union with Christ Jesus.
18 Those who believe in the Son are not judged; but those who do not believe have already been judged, because they have not believed in God's only Son.
5 But if our injustice commend the justice of God, what shall we say? Is God unjust, who executeth wrath? 6 (I speak according to man.) God forbid! Otherwise how shall God judge this world? 7 For if the truth of God hath more abounded through my lie, unto his glory, why am I also yet judged as a sinner? 8 And not rather (as we are slandered and as some affirm that we say) let us do evil that there may come good? Whose damnation is just.
There is not any man just. There is not any man just, viz... by virtue either of the law of nature, or of the law of Moses; but only by faith and grace.
11 There is none that understandeth: there is none that seeketh after God.
12 All have turned out of the way: they are become unprofitable together: there is none that doth good, there is not so much as one.
13 Their throat is an open sepulchre: with their tongues they have dealt deceitfully. The venom of asps is under their lips.
14 Whose mouth is full of cursing and bitterness:
15 Their feet swift to shed blood:
16 Destruction and misery in their ways:
17 And the way of peace they have not known.
18 There is no fear of God before their eyes.
19 Now we know that what things soever the law speaketh, it speaketh to them that are in the law: that every mouth may be stopped and all the world may be made subject to God. 20 Because by the works of the law no flesh shall be justified before him. For by the law is the knowledge of sin.
21 But now, without the law, the justice of God is made manifest, being witnessed by the law and the prophets. 22 Even the justice of God, by faith of Jesus Christ, unto all, and upon all them that believe in him: for there is no distinction. 23 For all have sinned and do need the glory of God. 24 Being justified freely by his grace, through the redemption that is in Christ Jesus, 25 Whom God hath proposed to be a propitiation, through faith in his blood, to the showing of his justice, for the remission of former sins, 26 Through the forbearance of God, for the showing of his justice in this time: that he himself may be just and the justifier of him who is of the faith of Jesus Christ.
27 Where is then thy boasting? It is excluded. By what law? Of works? No, but by the law of faith. 28 For we account a man to be justified by faith, without the works of the law. By faith, etc... The faith, to which the apostle here attributes man's justification, is not a presumptuous assurance of our being justified; but a firm and lively belief of all that God has revealed or promised (Hebrews 11). A faith working through charity in Jesus Christ (Galatians 5:6). In short, a faith which takes in hope, love, repentance, and the use of the sacraments. And the works which he here excludes, are only the works of the law: that is, such as are done by the law of nature, or that of Moses, antecedent to the faith of Christ: but by no means, such as follow faith, and proceed from it. 29 Is he the God of the Jews only? Is he not also of the Gentiles? yes, of the Gentiles also. 30 For it is one God that justifieth circumcision by faith and uncircumcision through faith. 31 Do we then, destroy the law through faith? God forbid! But we establish the law."