It's always a joy when Allah blesses you with a child. Children bring happiness and joy, but also trials and great responsibilities. One of the very first duties you have toward your new child, besides physical care and love, is to give your child a name that carries honor and Islamic meaning behind it.
It is reported that the Prophet (peace be upon him) said: "On the Day of Resurrection, you will be called by your names and by your fathers' names, so give yourselves good names." (Hadith Abu Dawud)
(A) When to Name the Child:
The ahaadeeth about when the child is to be named fall into two classes:
(1) Those which mention naming the child on the seventh day after the birth. Like the hadeeth of Samurah - radiyallaahu 'anhu - who said: Allah's Messenger said: <Every child is held in pledge for his' Aqeeqah which is sacrificed for him on his seventh day, and he is named on it and his head is shaved>1
And the hadeeth that the Messenger ordered that the child be named on the seventh day, that the harm be removed from him and the sacrifice (the 'Aqeeqah) be performed.2
(2) And those which indicate naming the child on the day of its birth. From these is the hadeeth of Anas-radiyallaahu 'anhu who said: Allah's Messenger (peace be upon him) said: <A boy was born to me this night and I have given him the name of my forefather Ibraaheem.>3 Allah's Messenger (peace be upon him) also named 'Abdullaah ibn Abee Taihah4. another baby was brought to him after birth and he called it al-Mundhir5 and there are many examples like this.
So from the previous ahaadeeth we can see that the time for giving the name is something flexible - and all praise and thanks are for Allah - so it may be named on the day of the birth, or delayed until the seventh day after birth - just as it is allowed between the two and later on. However, the time when it is recommended to name the child is the seventh day after the birth since that occurs in the words of the Prophet (peace be upon him) and so it is
taken to be a recommendation, and the ahadeeth mentioning the day of its birth report the Prophet's action - and are, therefore, taken to show & what is permissible.