Yaakov could not feel the same confidence in his conflict with Esav as he did when confronting Lavan because of the degree of guilt – be it perceived or actual – that he bore with regard to his strained relationship with his brother.
Parashat Vayishlach begins by telling of Yaakov's discovery that his brother, Esav, was approaching with an army of four hundred men. Yaakov's response is characterized by fear and dread, and he instantly divides his family and belongings, offers an impassioned plea to God for assistance, and sends his brother expensive gifts accompanied by a message of submission and appeasement.
Yaakov's apprehension about this anticipated confrontation with his brother seems to contrast sharply with the manner in which he had approached his conflict with his uncle and father-in-law, Lavan. Towards the end of Parashat Vayetze (31:36-55), we read of Yaakov's harsh exchange with Lavan, who responded by agreeing to a peaceful settlement. There Yaakov speaks with confidence, conviction and poise, as he forcefully presents his claims and grievances against his wily, conniving father-in-law. In his message to Esav, by contrast, Yaakov speaks with almost self-deprecating submission, repeatedly referring to himself as Esav's servant and to Esav as his master.
Rav Shimshon Refael Hirsch, in a brief but trenchant passage in his commentary, attributes Yaakov's different approaches to his two nemeses to the different circumstances surrounding these conflicts:
And how different is Jacob's attitude to Esau to what it was to Laban. We can recognize what strength the consciousness of innocence gives, and what an oppressive feeling even an appearance of guilt awakens. Twenty years endurance of a fight against wrong which you innocently have to bear do not have such a depressing effect as one minute's feeling towards somebody whom we know feels hurt by us, and who may not see the motive which, though it may not justify our action, can at least excuse it.
According to Rav Hirsch, Yaakov's forceful, confident words to Lavan were spoken from the unquestionable moral high-ground. Both he and Lavan knew without doubt that he – Yaakov – was the innocent victim of twenty years of devious schemes and machinations. In a sense, Rav Hirsch asserts, fighting such a battle is far easier than the conflict Yaakov now confronts after taking leave of Lavan – his conflict with his vengeful brother. Yaakov knows full well that he bears – in Rav Hirsch's words – at least "an appearance of guilt."
Even assuming that his "theft" of Esav's blessing was justified in light of Yitzchak's mistaken image of Esav, as is traditionally explained, there is still some legitimate basis for Esav's resentful feelings towards his brother. Yaakov could not feel the same confidence in his conflict with Esav as he did when confronting Lavan because of the degree of guilt – be it perceived or actual – that he bore with regard to his strained relationship with his brother. This uneasiness yielded, in Rav Hirsch's words, a "depressing effect" that undermined Yaakov's conviction and resolve, and resulted in the fear and apprehension described towards the beginning of this parasha.