Shaykh Muhammad ibn Sālih al ‘Uthaymīn (rahimahullāh) said,

The wisdom behind fasting is not that a person merely prevents himself from the grace of Allāh (‘azza wa jal), such as food, drink and sexual relations; however the wisdom behind fasting is something greater than that, it is (that you attain) the taqwa of Allāh, as Allāh (tabāraka wa ta’āla) said when he mentioned the obligation of fasting

‎[البقرة:183] ‎{ لَعَلَّكُمْ تَتَّقُونَ }

That you may become al-Muttaqūn [the pious and righteous persons who fear Allah much (abstain from all kinds of sins and evil deeds which He has forbidden) and love Allah much (perform all kinds of good deeds which He has ordained)]. Al-Baqarah: 183

At-Talīq ‘ala Risālah Haqīqah as-Siyām pgs. 12-13