SB 4.24.79

gītaṁ mayedaṁ naradeva-nandanāḥ
 parasya puṁsaḥ paramātmanaḥ stavam
japanta ekāgra-dhiyas tapo mahat
 caradhvam ante tata āpsyathepsitam
Synonyms: 
gītam — sung; mayā — by me; idam — this; naradeva-nandanāḥ — O sons of the King; parasya — of the Supreme; puṁsaḥ — Personality of Godhead; parama-ātmanaḥ — the Supersoul of everyone; stavam — prayer; japantaḥ — chanting; eka-agra — perfect attention; dhiyaḥ — intelligence; tapaḥ — austerities; mahat — great; caradhvam — you practice; ante — at the end; tataḥ — thereafter; āpsyatha — will achieve; īpsitam — the desired result.
Translation: 
My dear sons of the King, the prayers I have recited to you are meant for pleasing the Supreme Personality of Godhead, the Supersoul. I advise you to recite these prayers, which are as effective as great austerities. In this way, when you are mature, your life will be successful, and you will certainly achieve all your desired objectives without fail.
Purport: 

If we persistently engage in devotional service, certainly all our desires will be fulfilled in due course of time.

Thus end the Bhaktivedanta purports of the Fourth Canto, Twenty-fourth Chapter, of the Śrīmad-Bhāgavatam, entitled “Chanting the Song Sung by Lord Śiva.”