Someone who believes in Christ and repents is no longer walking in darkness. They are no longer actively walking in sin. The proof of repentance (a change of heart) is a person who doesn't do the sinful works they did before they repented. They are accepted with God. His grace and my faith and repentance are enough to bring me into fellowship with God.
But in every nation he that feareth him, and worketh righteousness, is accepted with him.
Acts 10:35
Is there forgiveness that comes with repentance or only with baptism? Well, I know for sure remission of sins comes with baptism, that is forgiveness, a literal washing away and cleansing of our hearts, a spiritual circumcision.
Are we saved if we don't have this circumcision? I don't think so. He that believeth and is baptized shall be saved.
But does our relationship change with God when we believe and repent? Definitely! What is that change? Our way of thinking changes which is seen by a change in how we act. Although I'm not sure how our standing "positionally" with God is changed, I do know it is enough of a change to warrant God filling us with his Spirit.
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His banner over me is LOVE....

My soul followeth hard after thee....Love one another with a pure heart
fervently.

Jesus saith unto her, Said I not unto thee, that, if thou wouldest believe, thou shouldest see the glory of God?
To be a servant of God, it will cost us our total commitment to God, and God alone. His burden must be our burden... Sis Alvear