[Irisshlass]

and KNEW HER NOT TILL she had brought forth her firstborn son; and she called his name Jesus.

Till does not indicate a change in behavior...

Romans 8
22 For we know that the whole creation (1) groans and suffers the pains of childbirth together until now.

1 Timothy 4
13 (1) Until I come, give attention to the public (2) reading of Scripture, to exhortation and teaching.

1 Timothy 6
14 that you keep the commandment without stain or reproach until the (1) appearing of our Lord Jesus Christ,

Revelation 2
25 'Nevertheless (1) what you have, hold fast (2) until I come

2 Samuel 6
23 Michal the daughter of Saul had no child to the day of her death.

[Cleburne]

un·til   
prep. 
Up to the time of: We danced until dawn. 
Before (a specified time): She can't leave until Friday. 
Scots. Unto; to. 

conj. 
Up to the time that: We walked until it got dark. 
Before: You cannot leave until your work is finished. 
To the point or extent that: I talked until I was hoarse. 

Till is the original form of until, so the definitions are the same. I do not have my Greek interlinear or gloss with me, and am too lazy to run upstairs to get it:) At any rate, I see "knew her not till" as implying that Joseph "did not know her" until after she had brought forth her son- why would such a phrase be included if he did not "know her" afterwards? It seems terribly straightforward to me.

[RnMomof7]

None of that scripture address the issue...you are just throwing stuff out there now Irish..