Praise be to Allaah.
It was proven that the Prophet (peace and blessings of
Allaah be upon him) said: “When Sha’baan is halfway through, do not fast.”
Narrated by Abu Dawood (3237); Ibn Hibaan (1651); classed as saheeh by
al-Albaani in Saheeh al-Tirmidhi.
There are some exceptions from this prohibition, as follows:
1 –One who has a habit of fasting, such as a man who
habitually fasts on Mondays and Thursdays, which he may do even after
halfway through Sha’baan. The evidence for that is the words of the Prophet
(peace and blessings of Allaah be upon him), “Do not anticipate
Ramadaan by fasting one or two days before it, except a man who fasts
regularly, who should observe his usual fast.” Narrated by al-Bukhaari,
1914; Muslim, 1082.
2 – A person who started fasting before halfway through
Sha’baan, and connects what comes after the halfway point to what came
before. This is not included in the prohibition either. The evidence for
that is the words of ‘Aa’ishah (may Allaah be pleased with her) who said:
“The Messenger of Allaah (peace and blessings of Allaah be upon him)
used to fast all of Sha’baan and fast all of Sha’baan except a little.”
Narrated by al-Bukhaari, 1970; Muslim, 1165. This version narrated by
Muslim.
Al-Nawawi said: “He used to fast all of Sha’baan and fast all
of Sha’baan except a little.” The second phrase is an explanation of the
first, pointing out that by “all” what is meant is “most”.
This hadeeth indicates that it is permissible to fast after
halfway through Sha’baan, but only for one who joins that to what came
before the halfway point.
3 – An exception from this prohibition is also made for one
who is making up missed Ramadaan fasts.
Al-Nawawi (may Allaah have mercy on him) said in
al-Majmoo’ (6/399):
Our companions said: it
is not correct to fast on the “day of doubt” just before Ramadaan, and there
is no difference of scholarly opinion on this point … But if a person fasts
it to make up a missed day or to fulfil a vow, or as an expiation, that is
acceptable, because if it is permissible to observe a voluntary fast on that
day, it is more likely to be permissible to observe an obligatory fast… and
if a person has to make up a day from Ramadaan, then he has to fast it,
because the time left for him to make it up has become very short.
The “day of doubt” is the thirtieth of Sha’baan if it has not
been possible to sight the moon of the thirtieth because of cloud, fog, etc.
It is called the “day of doubt” because there is some doubt concerning it –
is it the last day of Sha’baan or the first day of Ramadaan?
In conclusion:
There is nothing wrong with making up a missed Ramadaan fast
in the last half of Sha’baan. This is not included in the prohibition of the
Prophet (peace and blessings of Allaah be upon him) on fasting after
halfway through Sha’baan.
So your fasting of those three days is valid, and you have to
fast the remaining days before Ramadaan begins.
And Allaah knows best.