All sins are forgiven at the point of salvation: past, present and future ... (Protestants & Catholics: Do They Now Agree?, The Ankerberg Theological Research Institute, 1994, p. 99).
Ankerberg and Weldon teach all of our future sins after salvation are already forgiven even before they are committed and without confession to God, repentance and/or forgiving others who sin against us. To contrast this with the truth, let's see what the Bible says:
IF we confess our sins, he is faithful and just and will forgive us our sins and purify us from all unrighteousness (1 Jn. 1:9).
He who conceals his sins does not prosper, but whoever confesses and renounces them finds mercy (Prov. 28:13).
For IF you forgive men when they sin against you, your heavenly Father will also forgive you. But if you do not forgive men their sins, your Father will not forgive your sins (Matt. 6:14,15).
John Ankerberg and John Weldon are not alone. It is commonly taught among the eternal security teachers that one's future sins are already forgiven. Dear read, please know that once saved always saved is a demonic teaching. It is not associated with grace or the gospel, even though it is often presented as such. It is really another gospel. Remember:
We have come to share in Christ IF we hold firmly till the end the confidence we had at first. (Heb 3:14)