This holy month, in which divine prosperity and abundance enliven the earth, is the most profitable and beneficial month.The most important aspect of Shaban that increases its value is the fact that the reward of the worshipping performed in Shaban is three hundred times more than other months (except Ramadan).(1)
If the prayer performed at other times has ten rewards, prayer performed in Shaban has more than three hundred rewards. There are three hundred fruits of Paradise for each recited letter of the Quran.

The worshipping that we register in our deed books in these days of grants and mercy will act like a shield against the arrows of heedlessness, delusion and doubt thrown by the devil and become the source of our real peace. The rewards and good deeds that will compensate our mistakes and faults that we make without noticing or out of heedlessness are obtained abundantly during these days. In addition, that worshipping has the quality of being a shelter against the sins that may attack us in the future.
The Messenger of Allah (pbuh) worshipped and prayed more in this month than other months.

He praised it by saying
Shaban is my month.
Shaban cleanses the sins. (2)
When the month of Rajab came, he said "O Allah! Make the months of Rajab and Sha'ban blessed for us. (3)
He expressed the holiness of those months in his prayers.
One of the reasons why our Prophet showed respect to the month of Shaban was that Ramadan, the month of Quran, followed it. According to the narration of Hazrat Anas, our Prophet was asked:
"Oh Messenger of Allah, in which month other than Ramadan is fasting the most meritorious?"

Our Prophet answered it as follows,
The fasting performed in Shaban to show respect to Ramadan. (4)
According to the narration of the companions and especially Hazrat Aisha, our Prophet sometimes fasted in the whole month of Shaban and generally fasted on most of the days of Shaban. Besides, the Messenger of Allah (pbuh), who also fasted on other days especially on Mondays and Thursdays, often fasted due to many material and spiritual wisdoms of fasting.
Hazrat Aisha (may Allah be pleased with her) said the following:
The Messenger of Allah (pbuh) fasted so much in some months. We even thought he did not break his fast in that month. In some months, he broke his fast so much that we would say he did not fast on any days in this month. I did not see the Messenger of Allah (pbuh) fast in the whole month except Ramadan. I never saw him fast in any month more than he did in Shaban. (5)

Hazrat Aisha said the following in another narration:
"The Messenger of Allah (pbuh) never fasted in any month more than he did in Shaban. And he said the following:
Do the deeds that you can afford. Unless you get tired of them, Allah will not regard you as you have got tired. The best deed in the presence of Allah is the deed that a person constantly does even if it is little. (6)
In another narration in Ibn Majah, Hazrat Aisha said, “He (the Messenger of Allah) fasted in the whole month of Shaban and connected it with Ramadan.” (7) stating that he fasted more in that month.
Hadith scholars had the opinion that our Prophet fasted in the whole month of Shaban in some years and fasted on the most days of Shaban in some years from those two narrations. Besides, the Arabic word “kull” in the hadith which means “all” is used to express majority in Arabic.
If someone fasted on most days of a month, the expression “he fasted the whole month” was used.

The judgment that fasting in the whole month or on some days of Shaban is permissible is deduced from those two narrations.
Another wisdom of fasting, praying, giving alms and worshipping more in the month of Shaban is that getting ready bodily and spiritually for the month of Ramadan that will follow. Some people think,” We will worship more when Ramadan comes, anyway” and become heedless and lazy. The worshipping in Shaban prevents that heedlessness and laziness.
The Messenger of Allah (pbuh) points to it when he answers the question of Hazrat Usama ibn Zayd: Usama asks:
“Oh Messenger of Allah! I never saw you fast in any other month as much as you did in Shaban.”
The Messenger of Allah (pbuh) stated the following:
This month is between Rajab and Ramadan; People are ignorant of this month, which is between Rajab and Ramadan. It is the month in which the deeds are presented to the Lord of the Worlds. I want my deeds to be presented to Allah when I am fasting.(8)
If we appreciate these holy days and render our days and nights blessed and fruitful spiritually, we will benefit from the abundance and prosperity f this month more. The fasting performed in those months is not fard or wajib (obligatory); it is sunnah. We should try to fast in order to obtain rewards by following our Prophet.
May Almighty Allah make us benefit from the light and prosperity of the month of Shaban in the maximum degree. Amin.
References

1) Şualar, (Rays) p. 416.

2) Khashful Khafa. 2:9

3) Musnad, 1:259

4) Tirmidhi, Zakat: 28.

5) Bukhari, Sawm: 51.

6) Muslim. Siyam: 177.

7) Ibn Majah, Sawm: 4.

8) Nasai, Sawm: 70.