Hi. I know that there is a din that the Tefillin shel rosh must be behind the hairline, but does that mean that all of the shel rosh must be behind the hairline? Meaning if you have a sort of V-shaped hairline or wavy one, must you make sure that the shel rosh is entirely behind the hairline, or is it good enough if just part of it is?
and are there any mekoros for this
Thank you so much
The place that we have to put the Tefillin, is on the part of the head that it is normal for hair to grow from there, but it doesn’t specifically have to be in the hair itself. If this part of the head is where others hairline starts from, then that it the correct place to put the Tefillin (otherwise what should a bald man do?). If you have doubt exactly where it is, you can move the Shel Rosh back a little bit, just to be sure.
O:CH 27-9 M:B 33, Daas Noteh 3-311 ftnt. 447