Halocho #428 Rosh Chodesh is on Sunday and Monday

This Shabbat is "Shabbat Mevarchim".

Rosh Chodesh Marcheshvan will be on Sunday and Monday

There's an ancient custom to bless the upcoming month on the Shabbat before Rosh Chodesh, before Mussaf.

This is not to be confused with Sanctifying the Month that was done by the Sanhedrin when the new moon appeared.

Nevertheless, the custom is to stand when the Chazzan announces which day(s) will be Rosh Chodesh, since the sanctification of the month was done while standing.

Source: Mishna Brura 417:1

This week's Haftarah is "Machar Chodesh" - "And Jonathan says to him (David): tomorrow is Rosh Chodesh" from Shmuel-1 20:18

Previous Shabbat-related posts can be reviewed at http://halocho.blogspot.com/search/label/Shabbos

Shabbat Shalom uMevorach

- Danny,
 Thursday, 27 Tishrei 5770