CC Madhya 13.159
eta tāṅre kahi kṛṣṇa, vraje yāite satṛṣṇa,
eka śloka paḍi’ śunāila
sei śloka śuni’ rādhā, khāṇḍila sakala bādhā,
kṛṣṇa-prāptye pratīti ha-ila
eta — so much; tāṅre — unto Rādhārāṇī; kahi — speaking; kṛṣṇa — Lord Kṛṣṇa; vraje — in Vṛndāvana; yāite — to go; sa-tṛṣṇa — very anxious; eka śloka — one verse; paḍi’ — reciting; śunāila — making Her hear; sei śloka — that verse; śuni’ — hearing; rādhā — Śrīmatī Rādhārāṇī; khāṇḍila — disappeared; sakala — all kinds of; bādhā — hindrances; kṛṣṇa-prāptye — in achieving Kṛṣṇa; pratīti ha-ila — there was assurance.
While speaking to Śrīmatī Rādhārāṇī, Kṛṣṇa became very anxious to return to Vṛndāvana. He made Her listen to a verse which banished all Her difficulties and which assured Her that She would again attain Kṛṣṇa.
CC Madhya 13.160
mayi bhaktir hi bhūtānām
diṣṭyā yad āsīn mat-sneho
mayi — unto Me; bhaktiḥ — the nine kinds of devotional service, such as śravaṇa, kīrtana and smaraṇa; hi — certainly; bhūtānām — of all living entities; amṛtatvāya — for becoming eternal associates of the Lord; kalpate — is quite befitting; diṣṭyā — by good fortune; yat — whatever; āsīt — there was; mat-snehaḥ — love and affection for Me; bhavatīnām — of all you gopīs; mat-āpanaḥ — the cause for getting Me back.
Lord Śrī Kṛṣṇa said: “Devotional service unto Me is the only way to attain Me. My dear gopīs, whatever love and affection you have attained for Me by good fortune is the only reason for My returning to you.”