A friend of mine, he reverted to Islam a year ago, asked me "Why do muslims fear of Allah? We should love Allah without fear right?". I tried to explain to him, we must understand by context.
Remembering Allah with the heart, it brings to the heart serenity and peace...
The fear of not being accepted because Allah says: Allah only accepts from those who fear.[Maidah: 27]
The fear of showing off, for Allah says: They have been instructed to worship Allah sincerely; religion is for Him alone.[Bayinah: 5]
The fear of preserving the good deed because Allah says: Whoever brings a good deed shall have ten times its reward. [An`am: 161]
The fear of being deserted in performing good deeds, for Allah says: My reconciliation (with good) is only through Allah; it is upon Him that I trust and it is to Him that I resort.[Hud: 88]
Ghazali (rahmatullahi `alayhi) says: Fear rips away desires and muddens luxuries so that cherished sins become reprehensible, just as a honey loveris repelled by it when he learns that it has poison in it. This is how fearburns desires; disciplines the organs; subordinates the heart and gives it tranquility. It also enables the heart to rid itself of pride, hatred, andenvy; and it leaves it absorbed in it (fear). Hence, the heart becomespreoccupied with its own worries and looks towards its best interest in thelong run. It is then engaged in only matters like meditation, self-analysisand struggle. It cherishes its time and moments. [Ihya: 4/160]