First Nṛsiṁhānanda Brahmacārī contemplated a broad road starting from the city of Kuliyā. He bedecked the road with jewels, upon which he then laid a bed of stemless flowers. He mentally decorated both sides of the road with bakula flower trees, and at intervals on both sides he placed lakes of a transcendental nature. These lakes had bathing places constructed with jewels, and they were filled with blossoming lotus flowers. There were various birds chirping, and the water was exactly like nectar.
Śrīla Nṛsiṁhānanda Brahmacārī was a great devotee of Lord Caitanya Mahāprabhu; therefore when he heard that from Kuliyā, Śrī Caitanya Mahāprabhu was going to Vṛndāvana, although he had no material wealth he began to construct within his mind a very attractive path or road for Caitanya Mahāprabhu to traverse. Some of the description of this path is given above. But even mentally he could not construct the road beyond Kānāi Nāṭaśālā. Therefore he concluded that Caitanya Mahāprabhu would not go to Vṛndāvana at that time.
For a pure devotee, it is the same whether he materially constructs a path or constructs one within his mind. This is because the Supreme Personality of Godhead, Janārdana, is bhāva-grāhī, or appreciative of the sentiment. For Him a path made with actual jewels and a path made of mental jewels are the same. Though subtle, mind is also matter, so any path-indeed, anything for the service of the Lord, whether in gross matter or in subtle matter-is accepted equally by the Supreme Personality of Godhead. The Lord accepts the attitude of His devotee and sees how much he is prepared to serve Him. The devotee is at liberty to serve the Lord either in gross matter or in subtle matter. The important point is that the service be in relation with the Supreme Personality of Godheand. This is confirmed in the Bhagavad-gītā (9.26):
patraṁ puṣpaṁ phalaṁ toyaṁ
yo me bhaktyā prayacchati
tad ahaṁ bhakty-upahṛtam
“If one offers Me with love and devotion a leaf, a flower, a fruit or water, I will accept it.” The real ingredient is bhakti (devotion). Pure devotion is uncontaminated by the modes of material nature. Ahaituky apratihatā: unconditional devotional service cannot be checked by any material condition. This means that one does not have to be very rich to serve the Supreme Personality of Godhead. Even the poorest man can equally serve the Supreme Personality of Godhead if he has pure devotion. If there is no ulterior motive, devotional service cannot be checked by any material condition.
Ref >> Srila Prabhupada Vani.