“And you shall love Hashem your G-d” (Devarim 6,5)
It is a positive commandment to love the Holy One, blessed be He, as it says “and you shall love Hashem your G-d”. The substance of this commandment is that we should think and contemplate the instructions and works of Hashem until we come, to the best of our ability, to attain a level close to Him, to bask in the delight of His presence and this is the special love (mentioned here). Chazal say “It says “and you shall love” – we don’t know how a person can come to love G-d! Therefore it says “and these things which I am commanding you today should be on your heart” for through them you can recognise the One who spoke and the world came into being. That is to say, that through contemplation of the Torah, of necessity (automatically) love will settle in the heart of a person. Chazal say that this love will obligate a person to arouse himself to serve Hashem as we find with Avraham Avinu.
The roots of this commandment are well known -that a person cannot fulfil the commandments of Hashem, may He be blessed well, unless he loves Him.
The laws of this commandment are: that it is fitting for a person to concentrate all his thoughts and all his aims towards loving Hashem and he should constantly think in his heart that everything that he has in the world, whether it is riches, sons and daughters, a position and honour, all of this is nothing at all in comparison with His love, may He be blessed. And he should toil constantly, all day, seeking wisdom to reach this knowledge. The end point is that he must strive to the best of his ability, to accustom the thoughts of his heart to (focus on) His faithfulness and His oneness until there is not a single minute in his waking hours neither by day or by night when he does not remember the love of His Master with his entire heart.
This commandment applies in every place, at every time, to men and women, and one who transgresses this and fixes his thoughts on physical things and the emptiness of this world, not for the sake of Heaven but just in order to enjoy them or to receive honour in this world of falsehood and to make his own name great and does not do it with the intention of benefiting the good and strengthening the righteous, is annulling this positive commandment and his punishment is great.
This is one of the commandments which is continually incumbent on a person forever.