Saying “Thank you” is not Vedic. There is no real word for it in Sanskrit. The word ‘dhanyavāda’ being used in modern India for ‘thank you’ is introduced to facilitate westerners only, but can’t be found used in śāstra. People who are related in love or friendship do not say ‘thank you’ to each other. It is showing a distant relationship only. Of course, we do express gratitude, as Uddhava Mahāśaya did in Śrīmad Bhāgavata (11.29.6) after Śrī Kṛṣṇa spoke the Uddhava-gīta to him –
naivopayanty apacitiṁ kavayas taveśa
brahmāyuṣāpi kṛtam ṛddha-mudaḥ smarantaḥ
yo ’ntar bahis tanu-bhṛtām aśubhaṁ vidhunvann
ācārya-caittya-vapuṣā sva-gatiṁ vyanakti
“O my Lord! Intelligent persons can not fully express their indebtedness to you, even if they were endowed with the lifetime of Brahmā, because on remembering what you have done for them, their joy increases even more: appearing externally as Guru and internally as Paramātma, you reveal the supreme destination to them.”
Bhakta – „Some say this verse and the song „Caksu dān dilo ye, janme janme prabhu se‘ means that guru-tattva appears in another form in the next life to a śiṣya who did not attain perfection yet.“
Advaitadas – „The words ‚ye‘ and ‚se‘ refer to an individual person, not that anyone else becomes the Guru in the next life. That happens to casual śiṣyas, not to loving śiṣyas. For loving śiṣyas Śrī Gurudeva will re-appear as exactly the same person. How can it be otherwise? Kṛṣṇa says in Bhagavad-gītā (8.6) – yaṁ yaṁ vāpi smaran bhāvan tyajantyante kalevaram. „Whatever bhāva you contemplate, when you leave your body....“ You meditated on a Guru with a certain form, features and characteristics your whole life and as a result you will get another Guru in the next life? Sadā tad-bhāva bhāvita. „Due to always contemplating that sentiment“, tam tam evaiti, „You will surely attain that‘. For a devotee who abandoned bhakti-mārga there will be no bhakti-guru next life, for a casual śiṣya it may be anyone, for a loving śiṣya Gurudeva will reappear in his selfsame form and for a siddha śiṣya Gurudeva appears as guru-rūpa sakhī only. Nikuñja yūnoḥ rati-keli-siddhyaiḥ yā yālibhir yuktir apekṣanīya.
Ashamed of never having seen anything yet? These are words of hope (āśā-vāṇī) -
asphūrtitaḥ kathāto'pi śrīmad-vṛndāvane vasa
“Even if one has no divine revelations, one should still engage in Kṛṣṇa-kathā, living in Śrī Vṛndāvana." (Vṛndāvana Mahimāmṛta 8.42)
Lamenting about one's tapasya
Bragging about one's tapasya
Both will dim Hari's satisfaction with them.