The Best Invocation and Supplication to Allah
 

جَابِرَ بْنَ عَبْدِ اللَّهِ رضى الله عنهما يَقُولُ سَمِعْتُ رَسُولَ اللَّهِ -صلى الله عليه وسلم- يَقُولُ « أَفْضَلُ الذِّكْرِ لاَ إِلَهَ إِلاَّ اللَّهُ وَأَفْضَلُ الدُّعَاءِ الْحَمْدُ لِلَّهِ »

Jabir ibn Abdullah (may Allah be pleased with them) said: “I heard the Messenger of Allah (peace and blessings be upon him) say the best invocation to say is there is absolutely no deity worthy of worship but Allah. And the best supplication to say is all praises belong to Allah.”

Collected by At-Tirmithi (3383) Ibn Majah (1249) and others. Graded as being Hasan by Imam At-Tirmithi

Explanation:

“The invocation to say is there is absolutely no deity worthy of worship but Allah” This means: It’s the best invocation because this is the word of Tawheed. And nothing can compare to the word of Tawheed. The word of Tawheed is what separates Iman from Kufr. The word “ La illaha il Allah” connects the heart to Allah and separates it from all other deities. The word of Tawheed is the best purification for the soul. It cleanses man’s heart and soul, and rids it of all the wickedness of Shirk and Kufr. Furthermore saying the words of Tawheed drives away Shaytaan.

The best supplication to say is all praises belong to Allah.” These words mean: It’s the best because it’s a supplication and supplication is equivalent to remembering Allah-Thikr. Supplication is to seek a need from Allah. Praising Allah includes invocation and supplication. Whoever praises Allah praises Him for the blessing Allah has given him. And praising Allah for the blessing is asking for more. This is the pillar of gratitude. Allah says: If you thank Me I will give you more” [ Ibrahim 7]

Taken from Tuhfatul Ahwathee Sharh Jami’ At-Tirmithi for the numbered hadeeth above.