सर्वधर्मान्परित्यज्य मामेकं शरणं व्रज। अहं त्वा सर्वपापेभ्यो मोक्षयिष्यामि मा शुचः ॥

sarva-dharmān parityajya mām ekaṁ śharaṇaṁ vraja ahaṁ tvāṁ sarva-pāpebhyo mokṣhayiṣhyāmi mā śhuchaḥ

Abandoning all duties come unto Me alone for shelter; sorrow not, I will liberate thee from all sins.

In plain words: Krishna tells Arjuna to let go of every other duty and come to him alone for shelter. He says not to worry, because he will free Arjuna from all his sins.