Praise be to Allaah.
Knowing the Beautiful Names of Allaah is very important indeed, for the following reasons:
Knowledge of Allaah and His Names and Attributes is the noblest and best of all knowledge, because the level of honour of any kind of knowledge has to do with the object of knowledge, and the object of knowledge in this case is Allaah, may He be glorified and exalted, through His Names, Attributes and Deeds. Occupying oneself with seeking this knowledge and studying it properly is the pursuit of the highest objective, and acquiring this knowledge is one of the best gifts a person may be given. Because the Prophet (peace and blessings of Allaah be upon him) explained it very clearly and was very keen to do so, the Sahaabah never disputed in this matter as they did over some of the rulings (ahkaam).
Knowing Allaah makes a person love and fear Him, and put his hope in Him, and be sincere towards Him in his actions. This is the essence of human happiness. There is no way to know Allaah except by knowing His Most Beautiful Names and seeking a proper understanding of their meanings.
Knowing Allaah by His Most Beautiful Names increases ones faith, as Shaykh Abd al-Rahmaan ibn Sadi (may Allaah have mercy on him) said: Believing in and knowing the Most Beautiful Names of Allaah includes the three types of Tawheed: Tawheed al-Ruboobiyyah (Unity of Divine Lordship), Tawheed al-Uloohiyyah (Unity of the Divine Nature) and Tawheed al-Asma wal-Sifaat (Unity of the Divine Names and Attributes). These three types of Tawheed form the essence and joy of faith (the word translated here as joy implies peace and relief from stress), and this knowledge is the basis and purpose of faith. The more a person learns about the Names and Attributes of Allaah, the more his faith increases and the stronger his conviction becomes. (Al-Tawdeeh wal-Bayaan li Shajarat al-Eemaan by al-Sadi, p. 41).
Allaah created His creatures to know Him and worship Him. This is what is expected from them and what they are required to do, because as Ibn al-Qayyim (may Allaah have mercy on him) said: The key to the call of the Messengers, the essence of their Message, is knowing Allaah through His Names and Attributes and Deeds, because this is the foundation on which the rest of the Message, from beginning to end, is built. (Al-Sawaaiq al-Mursalah ala al-Jahamiyyah wal-Muattilah by Ibn al-Qayyim, 1/150-151). So when a person occupies himself with learning about Allaah, he is doing what he was created for, but if he ignores the matter, he is neglecting what he was created for. The meaning of faith is not merely to utter words without knowing Allaah, because true faith in Allaah means that the slave knows the Lord in Whom he believes, and he makes the effort to learn about Allaah through His Names and Attributes. The more he learns about his Lord, the more he increases in faith.
Knowledge of the Names of Allaah is the basis for all other knowledge, as Ibn al-Qayyim (may Allaah have mercy on him) said: Knowledge of the Most Beautiful Names of Allaah is the basis of all other kinds of knowledge, for the objects of all these other branches of knowledge were either created or commanded by Him (the various branches of knowledge either deal with objects created by Him or with the laws and guidance revealed by Him). The reason for creation and guidance is found in His Most Beautiful Names (because He is the Creator, He creates things; because He is the Guide to the Straight Path, He reveals guidance, and so on) Knowing the Most Beautiful Names is the basis of all objects of knowledge, because all knowledge stems from these Names (Badai' al-Fawaaid by Ibn al-Qayyim, 1/163).