”The best of’ the deeds or deed is the (observance of) prayer at its proper time and kindness to the parents.” (Buhari, Mevakiti’s-Salât)
As it is stated in the hadith-i Sharif, the best deed is to perform the prayer during the prayer times, because the most important thing after iman is the prayer.
“And I have chosen you, so listen to that which is inspired to you. Verily, I am Allah! There is none worthy of worship but I, so worship Me and offer prayer perfectly for My remembrance.” (Surah Taha,13-14)
Prayer is the first pillar of Islam that the Prophet (s.a.v.) mentioned after mentioning the testimony of faith, by which one becomes a Muslim. Therefore, Allah (c.c.) has set 5 prayer to worship Him and his forgiveness.
It is important in Islam to pray 5 times a day. Daily prayers are obligation for all Muslims. This is why nearly all of the world’s more than 1.2 billion Muslims turn toward Mecca every day on prayer times.
The Prophet (s.a.v) has also said Allah’s forgiveness and pleasure is closely related to the prayers:
”Allah has obligated five prayers. Whoever excellently performs their ablutions, prays them in their proper times, completes their bows, prostrations and khushu (complete sincerity) has a promise from Allah that He will forgive him. And whoever does not do that has no promise from Allah. He may either forgive him or punish him.” (Recorded by Malik)