- You must wash mayim achronim before Birkas Hamazon. Even if your hands are completely clean, they still may have the salt of Sodom on them. Any other time that you want to say a beracha you don’t need to wash (stam yodayim) unless your hands are dirty and it bothers you. (ShA – MB 1,22,23)
- If you have only a little bit of water, save some from the mayim rishonim to wash after the meal. If you have just enough water for mayim rishonim but there is more water nearby (1 mil travel), some poskim hold that you may not eat until you get water for mayim achronim. (MB 2)
- If there is no water in the vicinity (1 mil travel), you can eat and bentch first. Afterwards, go get the mayim achronim and wash. In this case it’s best to wrap your hands while you eat so your hands don’t touch the salt of Sodom. (MB 2 – ShaH 8)
- Do not wash mayim achronim onto the ground (even tiled) where people walk – there is ruach ra’a resting on the water which could harm passers-by. (ShA 2 – MB 4,6)
- You may wash mayim achronim under the table since people don’t walk there. Even if they move the table, by then the water will have dried up. (MB 4)
- If you don’t have a kli to wash into, wash over sticks or gravel so the water absorbs and doesn’t gather. (MB 6)
- Don’t empty the kli of mayim achronim onto the ground where people walk. (BeH “elloh”)
- Mayim achronim doesn’t work by dipping your hands into it. (MB 3)
- The water should not be warm. If all you have is warm water you can be maykil to use it, as long as it is not scalding hot. (ShA 3 – MB 7)
- Fulfil the opinion of the Gr”a to wash up until the big knuckles. If you don’t have enough water, just wash up until the middle joint of your fingers (and the first joint of the thumb). It’s bad just to put a few drops on your fingertips. (MB 10 – BeH “odd”)
- If your hands are dirty beyond the above stated joints, you must wash off also over there. (MB 10)
- Hold your fingers downwards so the water drips down carrying off the filth. (ShA 5)
- Who should begin washing mayim achronim?
- If there are 3-5 people at the meal, the one who leads the bentching should wash first and then look over the zimun etc. while the others are washing.
- If there are more than 5, let others wash until you get down to the last 5. Then let the leader wash fifth from last. This is to minimize the hefsek between netilla and Birkas Hamazon (the amount of time it takes to walk 22 amos) for the leader.
(ShA 6 – MB 12,13)
- These days everyone bentches along quietly with the leader who bentches out loud. It is therefore proper to minimize the hefsek between netilla and Birkas Hamazon for everyone (more than 5 people). Have many cups for mayim achronim on the table so they can wash at the same time. (BeH “min”)
- It is not considered an honor to give someone mayim achronim to wash before you. (ShA 6)
- It is best to dry after mayim achronim to fulfil the opinion of the Rambam. (MB 19)
- Mayim Achronim does not have many of the requirements of mayim rishonim:
- No minimum amount (The Gr”a used a r’viis.)
- No kli required.
- No koach gavra.
- No second pouring.
- Substance on the hand that blocks the water is okay.
- The water can be discolored.
- The water can be already used for melacha.
(MB 19,21)
- Any drink (except for wine) can be used for mayim achronim if water is not available. (ShA 9 – MB 20,21)
- If you are from those who do not have the custom to wash mayim achronim regularly, but you feel uncomfortable after a meal and feel like you want to wash your hands – you must wash mayim achronim! For that matter, if your hands are filthy during a meal and you need to say a beracha (on fruit or thunder etc.) wash first. (ShA 10 – MB 23 – ShaH 32)