Sya’ban is a special month for the Prophet SAW because the verse of the command to pray was revealed in this month (Al-Ahzab verse 56). Then in this month human deeds are lifted (to heaven) by Allah Ta’ala.
That is why the Prophet Muhammad shallallahu ‘alaihi wa sallam (SAW) made it a month of perfect worship and filled it with fasting. Ummul Mukminin Sayyidah ‘Aisyah radhiallahu’ anha said: “I have never seen Rasulullah SAW fast in one month as much as the fast he did in the month of Sya’ban, in which he fasted for a full month.” In another narration, “He fasted in the month of Sya’ban, except for a few days.” (Narrated by Muslim).
From Usamah bin Ziyad, he said, “I asked the Messenger of Allah, ‘O Messenger of Allah, I do not see you fasting as much as in the month of Sya”ban? He replied,’ Sya’ban is a month that human beings are forgotten, it is located between Rajab and Ramadhan. In that month human deeds are raised (to heaven) by Allah and I like when deeds are raised I am in a state of fasting. (HR. An-Nasai).
The reading of the intention of the fasting month of Shaban
نَوَيْتُ صَوْمَ غَدٍ عَنْ أَدَاءِ سُنَّةِ شَعْبَانَ لِلهِ تَعَالَى
Nawaitu Shauma Ghadin ‘An Adai Sunnati Sya’bana Lillaahi Ta’aalaa.
“I intend to fast the sunnah of Sya’ban tomorrow because of Allah Ta’ala.”
The scholars say, Rajab is the month to purify the body, the month of Sya’ban to purify the heart and Ramadhan to purify the soul / soul. So whoever purifies his body in the month of Rajab, purify his heart in the month of Sya’ban. Whoever purifies his heart in the month of Sya’ban then purify his soul / soul in the holy month of Ramadan. (Read Also: Welcome to Sya’ban, the month of Rasulullah, this is his priority)
Reference : https://kalam.sindonews.com/berita/1568407/70/bacaan-niat-puasa-sunnah-bulan-syaban