What is tahnik for a newborn?

Yes, it's a sunnah: tahnik is gently rubbing a little softened date on a newborn's palate. The Prophet ﷺ did it for babies brought to him, and Muslims have kept the practice ever since. It is recommended, not required, and your baby's safety and the advice of your midwife or doctor come first.

What tahnik is

The word comes from hanak, the Arabic for the palate, the roof of the mouth. Tahnik means chewing or softening a small piece of date until it's a soft paste, then rubbing a little of it on the baby's palate with a clean finger. It's usually done soon after birth, along with a dua for the baby.

What the hadith say

Abu Musa said: "A son was born to me and I took him to the Prophet ﷺ who named him Ibrahim, did tahnik for him with a date, invoked Allah to bless him and returned him to me" (Sahih al-Bukhari 5467). Anas brought the newborn Abdullah ibn Abi Talha to the Prophet ﷺ, who asked for dates, softened them in his own mouth and placed them in the baby's mouth, and the child began to lick them (Sahih Muslim 2144).

The Companions would bring their babies to him for this. It has been seen as a way of starting a child's life with a blessing and a sweet taste.

Who can do it?

Scholars generally recommend that it be done by a pious person, because the Companions sought the blessing of the Prophet ﷺ. But the Prophet's own blessing was unique to him, and there's no requirement to find a particular person. Parents commonly do it themselves, or ask a grandparent, imam or trusted friend. If no one is available, nothing is lost. The main thing is the dua you make for your child.

How to do it safely

Use a soft, pitted date, mashed with a drop of water, so it forms a smooth paste.
Use a tiny amount, about the size of a grain of rice, and rub it gently on the palate. Don't place a lump in the baby's mouth.
Wash your hands first. A newborn's immune system is fragile.
Ask your midwife or doctor first, especially in hospital. Premature babies, babies with low blood sugar, breathing or feeding problems, or those whose mothers have diabetes may need special care. If staff advise against it, skip it.
Use dates, not honey. Honey is not safe for babies under one year, so don't replace the date with it.

What to say

As in the hadith, make dua for the baby after tahnik. Something like "May Allah bless him/her and make him/her righteous" is enough, in any language. You can also say the adhan in the baby's right ear. See What do I whisper in my baby's ear after birth? For more duas, see What dua do I say for a newborn baby?

Tahnik belongs with the other early customs: giving a good name, the aqiqah and shaving the baby's head on the seventh day. None of them is required for your baby to be Muslim. See What is an aqiqah?

Key points

Tahnik is rubbing softened date on a newborn's palate.
It's a sunnah from Sahih al-Bukhari and Sahih Muslim, not an obligation.
A pious person is recommended, but parents can do it.
Use a tiny smear of date, never honey, and follow medical advice.

Tip: Bring two or three soft dates to the hospital in a clean container. If your midwife agrees, you can do it in the first hours without any fuss.