By the way, I checked the Stephens Textus Receptus (1550) and the 
Scrivener's Textus Receptus (1881) and both have the same reading as the 
Nestle-Aland 26th edition of the GNT.  In all three the aphiemi is in the 
second person plural aorist active subjunctive.  I'm using my computer so I 
don't have access to the textual apparatus of the NA 26th edition at hand 
so I'll take your word that aphiemi occurs in the present tense in some 
manuscripts.
However, "ean" with the subjunctive simply indicates a conditional 
sentence. The aorist tense usually indicates a punctiliar or snapshot event 
in the past.  However, according to Dana and Mantey, it can also indicate 
inception action.  That is, it begins with an event in the past and may 
have enduring results.  I would think, on further reflection, that this may 
be the intention of Matthew 6:14.  If we forgive and that forgiveness 
continues or endures (at some point in the past) then in the future the 
Father will forgive our sins.  The second occurrence is in the future 
tense.  This second forgiveness may indicate both future to the actual 
event of forgiveness or it may refer to the coming judgment.  I tend to 
think it is the former.   I haven't consulted any commentaries on this so 
I'm just giving my spin on it.
Sincerely in Christ,
Charlie Ray, 
Chaplain
1 Timothy 4:16
Watch your life and doctrine closely.
Persevere in them, because if you do,
you will save both yourself and your hearers.  (NIV).
chaplain@isgroup.net
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 * WR  # 461 * Sola Scriptura, Solus Christus, Sola Gratia, Sola Fide.
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