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Matanos Laevyonim are to be given on Purim during the daytime. One who sent Matanos Laevyonim on the night of Purim does not fulfill his obligation. [Based on Kabala it is to be given after the Megillah reading, as opposed to beforehand. However others write it is to be distributed before Davening.]
When during the day is one to distribute Matanos Laevyonim?
The Matanos Laevyonim may be distributed anytime throughout the day, beginning from sunrise up until sunset. In a time of need it may be distributed starting from Alos. If one did not yet distribute Matanos Laevyonim and it is already past sunset, then if it is still prior to nightfall one should still fulfill the Mitzvah.
May one give Matanos Laevyonim prior to Shacharis?
Yes. However some are particular to give Matanos Laevyonim after Shacharis in order so the blessing of Shehechiyanu count also for this Mitzvah. Nevertheless one is not to refrain from giving charity prior to Davening due to this reason, and is simply to give again after Davening.
Should one distribute Matanos Laevyonim prior to Mishloach Manos?
Some write that Matanos Laevyonim is to be distributed immediately after Shachris, prior to Mishloach Manos. Others write it is to be distributed after Mishloach Manos. Practically, whichever Mitzvah presents itself first is to be fulfilled and not delayed, and only if the opportunity has not yet arrived is one to follow one of the above orders.
May one give Matanos Laevyonim before Purim in order to fulfill his obligation?
Opinion of most Poskim: One may send Matanos Laevyonim to a pauper before Purim if the charity will arrive to him on Purim. If however it will arrive before Purim, one does not fulfill his obligation. However some Poskim rule that if one stipulates with the pauper that he can only use the money for his Purim needs, then it may be given even before Purim. Other Poskim however rule that if the money arrives before Purim, it is invalid, even if one stipulated with pauper beforehand.
*Needless to say according to all one may send Matanos Laevyonim before Purim even any scenario if one plans to distribute Matanos Laevyonim to two paupers also on Purim.
- To note that due to the above dispute some Matanos Laevyonim charity funds arrange that the moneys are considered a Pikadon [collateral] in the hands of the fund until they are distributed on Purim. Hence the money is not considered to have left the hands of the giver until Purim when his messenger distributes it for him.
May one eat prior to distributing Matanos Laevyonim?
Some Poskim rule it is forbidden to eat prior to fulfilling the Mitzvah of Matanos Laevyonim and Mishloach Manos, just like is the ruling by all Mitzvos. Others rule one may eat beforehand.
 M”A 695/13; Elya Raba 695/11; M”B 695/22
 Kaf Hachaim 694/18 based on Shaar Hakavanos
 Siddur Yaavetz states to give Matanos Laevyonim before Davening. Darkei Chaim Veshalom 849 states that the Munkatcher would distribute Mishloach Manos before Davening and after Davening.
 See Michaber 687/1 and the commentaries there, brought above in chapter 7 Halacha 5B regarding the times for the daytime Megillah reading, and the same would apply to the Mitzvah of Matanos Laevyonim.
 See Piskeiy Teshuvos 692/5; Chapter 7 Halacha 10 regarding intending on the Mitzvahs when reciting Shehechiyanu
 See Yesod Veshoresh Havoda 12/6 that one is to give Matanos Laevyonim prior to Shacharis. So writes also Siddur Yaavetz.
 Likkutei Maharich brought in Piskeiy Teshuvos 494/1
 Makor Chaim of Chavos Yair 695/4
 The reason: As this follows the order of the verse “Mishloach Manos” and then “Matanos Laevyonim”. [ibid]
 Betzeil Hachochma 6/81
 Aruch Hashulchan 694/2 [however see Aruch Hashulchan 695/17]; Ashel Avraham Butchatcher 694; Daas Torah 695/4; Beis Shearim 381; Chelkas Yaakov 1/102; Divreiy Yatziv 2/298; Kinyan Torah 4/86; Mishneh Halachos 4/87; Kaf Hachaim 694/15; Yad Ahron brought in Beir Heiytiv 695/7. They base their ruling on the M”A 694/1 that forbids giving it before Purim due to that perhaps the pauper will use it, or eat it, before Purim. This hence implies that if the pauper will use it on Purim the giver fulfills his obligation.
 M”A ibid, as perhaps if it is given before Purim the receiver will use it up prior to Purim.
 Divreiy Yatziv 2/298; Kinyan Torah 4/86; Mishneh Halachos 4/87
 Az Nidbaru 6/80
 The reason: As the Mitzvah is for the joy of the gift to be received by the pauper on Purim and here the joy was already received before Purim.
 Birkeiy Yosef 694; Aruch Hashulchan 695/17 [however see 694/2]; See Beir Heiytiv 695/7
 The reason: As it ends up that one did not actually give it on Purim.
 Biur Halacha 694 “Lishneiy Aniyim” based on Machatzis Hashekel
 The reason: As according to all one may have an emissary give money towards Matanos Laevyonim on his behalf. [Aruch Hashulchan 694/2; 695/16]
 Az Nidbaru 6/65; Shraga Hameir 3/113; Leket Yosher of student of Terumas Hadeshen states it is proper not to eat beforehand.
 Likkutei Maharich; Tzitz Eliezer 15/32; Mishneh Halachos 6/126; 7/92
 The reason: As eating on Purim is also a Mitzvah, and on the contrary, it comes first in the Pasuk.