The scriptures declare that only through “Bhakti” one can realize God, there is no other Way!
न साधयति मां योगो न साङ्ख्यं धर्म उद्धव।
न स्वाध्यायस्तपस्त्यागो यथा भक्तिर्ममोर्जिता॥
~ श्रीमद्भागवद् 11.14.20
Shri Krishna says I cannot be realized by Yoga, Sāṅkhya Knowledge, Pious Work, Vedic Study, Austerity or Renunciation. I am known only by Unalloyed Devotion (भक्तिर्ममोर्जिता).
अथात आनन्ददुघं पदाम्बुजं
हंसा: श्रयेरन्नरविन्दलोचन।
सुखं नु विश्वेश्वर योगकर्मभि-
स्त्वन्माययामी विहता न मानिन:॥
~ श्रीमद्भागवद् 11.29.3
Uddhav is saying to Lord Krishna, “Therefore O lotus-eyed Lord of the universe, in the end even elevated souls like हंस, परमहंस (स्वरूप में स्थित योगी, ज्ञानी आदि) happily takes shelter (being unable to overcome maya) of your lotus feet, which are the source of all divine bliss. But those who are proud of the achievements of their yoga and work, they do not take shelter of you and are defeated by your illusionary power maya.
भक्त्या मामभिजानाति यावान्यश्चास्मि तत्त्वत:।
ततो मां तत्त्वतो ज्ञात्वा विशते तदनन्तरम्॥
~ श्रीमद्भगवद्गीता 18.55
Only by loving devotion to Me does one come to know who I am in Truth. Then, having come to know Me, My devotee enters into full consciousness of Me.
पुरुष: स पर: पार्थ भक्त्या लभ्यस्त्वनन्यया।
यस्यान्त:स्थानि भूतानि येन सर्वमिदं ततम्॥
~ श्रीमद्भगवद्गीता 8.22
The Supreme Divine Personality is greater than all that exists. Although He is all-pervading and all living beings are situated in Him, yet He can be known only through Devotion.
भक्त्या त्वनन्यया शक्य अहमेवंविधोऽर्जुन।
ज्ञातुं द्रष्टुं च तत्त्वेन प्रवेष्टुं च परन्तप॥
~ श्रीमद्भगवद्गीता 11.54
O Arjun, by unalloyed devotion alone can I be known as I am, standing before you. Thereby, on receiving My divine vision, O scorcher of foes, one can know Me and see Me and enter into union with Me.
Every where it is repeated again & again that Only by loving Devotion can any one know God.
श्री रामचरितमानस Says
रामहि केवल प्रेम प्यारा, जान लेऊ जो जानन हारा।
Lord Shri Ram is only realized by Love. Reveal this truth to all those who really want to know.
Guru Nanak Dev Ji Says
हरि सम जग महान वस्तु नहीं, प्रेम पंथ सौ पंथ, सद्गुरु सम सज्जन नहीं, गीता सम नहीं ग्रंथ।
All different paths are difficult and take you only that far, it is only Bhakti which takes you all the way to God. It is simple and easy, God like a mother, herself nurse and nourish the devotee and take him in her lap. All one has to do is to have unflinching faith in God and surrender to him in love. His grace does the rest.
Bhagavad Gita Says
तद्विद्धि प्रणिपातेन परिप्रश्नेन सेवया।
उपदेक्ष्यन्ति ते ज्ञानं ज्ञानिनस्तत्त्वदर्शिन:॥
~ श्रीमद्भगवद्गीता 4.34
Learn the Truth by approaching a spiritual master. Inquire from him with reverence and render service unto him. Such an enlightened Saint can impart knowledge unto you because he has seen the Truth.
In Bhakti, it is most essential that we take shelter of a Guru who is well versed in the Scriptures (श्रोत्रिय) and God-Realized (ब्रह्मनिष्ठ), serve him, understand the correct principles and subtleties of Bhakti from him, and do practice under his guidance. Then welfare is certain, there is no doubt about it!
Jagadguru Shri Kripalu Ji Maharaj Says
मन मनमोहन भजन कर, सजन स्नेही मान।
बिनुहिन बुलाय अहै, जग विराग अरु ज्ञान॥