Why are fear and love incompatibles? Is God afraid of anything? Certainly, no! Well, it is so because He is almighty... And what of us? Here is John the Evangelist speaks about it: God Himself indwells in the one who loves, because God is love. And we thus have to be afraid of nothing. But if ever there is fear in us there (it is identified by the "torment"), then it is evident that love, God's presence in us is imperfect, insufficient.
There is another important moment here. The apostle John writes that love is manifested in the fulfillment of the commandments. Fear was the main motive for the fulfillment of the commandments in the Old Testament, and this fear paralyzed man. Indeed, commandments indicated what shouldn’t be done, and by longing to fulfill them, man was afraid of doing, in order not to do what is wrong. The new commandment, of which John writes, is formulated differently: do, love one another. The aspiration to fulfill this commandment frees man, manifests in him activity, initiative.