Zerizin Makdimin LeMitzvot
One of the principles of how to perform mitzvot involves a person's attitude towards when it is accomplished. Zerizin Makidimin Lemitzot is the value of having alacrity in observing mitzvot at the first available moment and not delaying in doing them. We learn this concept from Avraham who arose early in the morning to go sacrifice his son, Yitzchak, at the Akeida.
Similarly, the first Halacha we are instructed in the Shulchan Aruch tells us that a person must wake up in the morning "like a lion" to "serve his creator" that he should "wake up the dawn."  Even in the winter when one is cold and feels uncomfortable rising from his warm bed or if a person is tired, one should overcome his desire to remain in bed.
Not Passing Up Mitzvot
- There is a general rule that one may not pass over or delay doing a mitzvah that comes one's way. According to many poskim this is a Biblical principle, while others hold it is rabbinic.
- It only applies when one is deciding to do one of two mitzvot. However, if a mitzvah doesn't apply now there's no prohibition to pass over that mitzvah. Similarly, if one is faced with two mitzvot and one only has time to fulfill one of them then there is no prohibition to pass over a mitzvah. Rather one should do the mitzvah according to the following factors:
- One should do the mitzvah that is more severe such as tefillin more kadosh than tallit.
- If both are equally severe then choose the mitzvah that is more common.
- If they are equally common choose the mitzvah that expires first.
- If a mitzvah is more severe than another it takes precedence over another less severe mitzvah even if the less severe one expires sooner. For example, if on Erev Yom Kippur someone is in an army that would stop him from doing mitzvot and he can either take guard duty today and then fast tomorrow or take guard duty tomorrow and fulfill tefillin today he should take the guard duty today since the mitzvah to fast on Yom Kippur is more severe than tefillin.
- There is no consideration of not passing over a mitzvah if he wouldn't be involved in the mitzvah himself. For example, passing over the opportunity to watch a mitzvah so that it would be a greater publicity of the mitzvah isn't a prohibition.
- If someone can do the mitzvah later in a better fashion then one may delay it and it isn't considered passing over a mitzvah.
In Competition with Other Principles
- Many poskim hold that Hiddur Mitzvah trumps Zerizin. Others hold that Zerizin trumps Hiddur Mitzvah. For example, if you can say Kiddush Levana on Wednesday night but it would be nicer to say it on Motzei Shabbat because you will be wearing nice clothing it is better to wait. Others disagree. See Birkat_HaLevana#When_It_Should_Be_Said.
- Some say that Hiddur Mitzvah only trumps Zerizin if by waiting one can fulfill the same mitzvah in an enhanced fashion, however, if by waiting it is going to be a different mitzvah that one can fulfill in an enhanced fashion then one should do the first mitzvah available because of Zerizin.
- Brit Milah
- Brov Am Hadrat Melech
- Which Mitzvot take precedence?
- Yoma 28b, Rambam Milah 1:8
- Shulchan Aruch O.C. 1:1
- Mishna Brurah 1:1 Particularly in the summer, when the nights are shorter and one may be tired, one should make sure to rise to serve Hashem with alacrity. One should imagine himself as if going to a meeting with a king of flesh and blood in order to inspire himself to wake up on time.
- Chayei Adam 68:1 quotes Tosfot Yoma 33b and Tosfot Zevachim 51a who imply that ein ovrin al hamitzvot is Biblical unlike the Radvaz 1:529 who writes that it is rabbinic.
- Gevurat Ari (Yoma 15b)
- Chayei Adam 68:1
- Yoma 33, Chayei Adam 68:1
- Chayei Adam 68:1
- Kiddushin 29b, Magen Avraham 556, Chayei Adam 68:1
- Chayei Adam 68:1
- Yoma 70a, Chayei Adam 68:1
- Chayei Adam 68:1, Shulchan Aruch O.C. 429 regarding waiting for kiddush levana until motzei shabbat. See Gra who argues not to delay.
- Yikach Mitzvot 7:1 based on Trumat Hadeshen 35 and 269 as well as Divrei Malkiel 1:12.
- Yikach Mitzvot 7:1 based on Radvaz 4:1087, Sefer Chasidim 878, Panim Meirot 2:1, Avodat Hagershuni 12,
- Yikach Mitzvot 7:2 based on Chacham Tzvi 106 unlike the Chesed Lavraham 2:77 who doesn't distinguish between whether it is one mitzvah or two regarding Hiddur Mitzvah overriding Zerizin.