Bg 18.56

sarva-karmāṇy api sadā
kurvāṇo mad-vyapāśrayaḥ
mat-prasādād avāpnoti
śāśvataṁ padam avyayam
Synonyms: 
sarva — all; karmāṇi — activities; api — although; sadā — always; kurvāṇaḥ — performing; mat-vyapāśrayaḥ — under My protection; mat-prasādāt — by My mercy; avāpnoti — one achieves; śāśvatam — the eternal; padam — abode; avyayam — imperishable.
Translation: 
Though engaged in all kinds of activities, My pure devotee, under My protection, reaches the eternal and imperishable abode by My grace.
Purport: 

The word mad-vyapāśrayaḥ means under the protection of the Supreme Lord. To be free from material contamination, a pure devotee acts under the direction of the Supreme Lord or His representative, the spiritual master. There is no time limitation for a pure devotee. He is always, twenty-four hours a day, one hundred percent engaged in activities under the direction of the Supreme Lord. To a devotee who is thus engaged in Kṛṣṇa consciousness the Lord is very, very kind. In spite of all difficulties, he is eventually placed in the transcendental abode, or Kṛṣṇaloka. He is guaranteed entrance there; there is no doubt about it. In that supreme abode, there is no change; everything is eternal, imperishable and full of knowledge.