Although I cannot speak for all Evangelicals, since they just as every other person will have differing conceptions of Scriptures which are not definitive. I can, however, tell you what the Scriptures say concerning this and what my perception is.
Most Evangelicals that I know do believe, that after profession of faith, one's sins are forgotten forever, will no longer be charged against them. Basic to this belief is that Jesus paid our sin debt in full. So how do we get to the point of that belief?
Genesis 2:17 KJV But of the tree of the knowledge of good and evil, thou shalt not eat of it: for in the day that thou eatest thereof thou shalt surely die.
If we are to understand what is meant by that verse, we must first understand what surely die means. It cannot mean physical death since Adam and Eve both continued to exist in their physical forms just as before.
So let's look at:
Genesis 2:7 KJV And the LORD God formed man of the dust of the ground, and breathed into his nostrils the breath of life; and man became a living soul.
There a two distinct parts of that Scripture:
1.the physical body from the dust, but that was still not alive.
2.man became a living Soul.
When man received the breath of life, then his Soul was produced.
Understanding these things, it becomes apparent, that we now have to understand just what it is, and how Jesus can redeem our Souls:
Revelation 2:11 He that hath an ear, let him hear what the Spirit saith unto the churches; He that overcometh shall not be hurt of the second death.
Revelation 20:6 Blessed and holy is he that hath part in the first resurrection: on such the second death hath no power, but they shall be priests of God and of Christ, and shall reign with him a thousand years.
Revelation 20:14 And death and hell were cast into the lake of fire. This is the second death.
Revelation 21:8 But the fearful, and unbelieving, and the abominable, and murderers, and whoremongers, and sorcerers, and idolaters, and all liars, shall have their part in the lake which burneth with fire and brimstone: which is the second death.
The second death then is the eternal destruction of the Soul.
So how does Jesus save our sinful souls from eternal fire and how does repentance and our present sins fit into that redemption?
For this we must go to the sacrificial ceremonies God dictated to the Israelites.
Leviticus 1:2 through 4 KJV Speak unto the children of Israel, and say unto them, If any man of you bring an offering unto the LORD, ye shall bring your offering of the cattle, even of the herd, and of the flock. If his offering be a burnt sacrifice of the herd, let him offer a male without blemish: he shall offer it of his own voluntary will at the door of the tabernacle of the congregation before the LORD. And he shall put his hand upon the head of the burnt offering; and it shall be accepted for him to make atonement for him.
So let's consider this substitutionary sacrifice as compared to Jesus.
if any man (or woman) bring an offering to the Lord. Jesus is our offering: a male without blemish.
he shall offer it of his own voluntary will at the door of the tabernacle of the congregation before the LORD We offer Jesus as our willful sacrifice for our sins when we ask God's forgiveness based on our belief that his death on the cross is sufficient to atone for our sins. And it is at this point that I must say that that sacrifice is for future as well as past sins.
If his offering be a burnt sacrifice of the herd, let him offer a male without blemish Since Jesus is a burnt sacrifice in that he is suffering the eternal fire so that we do not have to.
And he shall put his hand upon the head of the burnt offering; and it shall be accepted for him to make atonement for him. This is the biggie Jesus is sacrificed not for any sin that he committed since he was without blemish (sin), but is accepted as atonement for our sins.
On several occasions Jesus told someone to go and sin no more. So then if Jesus was concerned with people sinning after being forgiven, what could cause him to tell them not to sin again?
To that, the Bible does not give us an explanation; however, I believe that there might be a good reason for his concern.
That reason could be that as I said before, his sacrifice atones not only for past sins but future sins also. Sine he is atoning for future sins is the punishment also future?
The most horrendous way that we could experience how awful our sins are is to witness whether or not:
Does Jesus have to feel the fire anew every time we sin?