Srimad Bhagavatam Canto 10, Chapter 47, Text 24

SB 10.47.24

dana-vrata-tapo-homa
 japa-svadhyaya-samyamaih
sreyobhir vividhais canyaih
 krsne bhaktir hi sadhyate
 
Translation: 
 
Devotional service unto Lord Krsna is attained by charity, strict vows, austerities and fire sacrifices, by japa, study of Vedic texts, observance of regulative principles and, indeed, by the performance of many other auspicious practices.
 
Purport: 
 
Srila Visvanatha Cakravarti explains the processes described here as follows. Dana: donations given to Lord Visnu and His devotees. Vrata: observing vows such as Ekadasi. Tapas: renunciation of sense gratification for Krsna’s sake. Homa: fire sacrifices dedicated to Visnu. Japa: privately chanting the holy names of the Lord. Svadhyaya: study and recitation of Vedic texts such as the Gopala-tapani Upanisad.
Srimad Bhagavatam Canto 10, Chapter 47, Text 23
Srimad Bhagavatam Canto 10, Chapter 47, Text 25