B.G 4.19
यस्य सर्वे समारम्भाः कामसङ्कल्पवर्जिताः। ज्ञानाग्निदग्धकर्माणं तमाहुः पण्डितं बुधाः ॥१९॥
yasya sarve samārambhāḥ kāmasaṅkalpavarjitāḥ। jñānāgnidagdhakarmāṇaṁ tamāhuḥ paṇḍitaṁ budhāḥ ॥19॥
[यस्य सर्वे समारम्भाः काम सङ्कल्प वर्जिताः। ज्ञान अग्नि दग्ध कर्माणं तम् आहुः पण्डितं बुधाः॥
yasya = whose; sarve = all; samārambhāḥ = undertakings; kāma = desires; saṅkalpa = resolutions; varjitāḥ = devoid of;। jñāna = knowledge; agni = of fire; dagdha = burnt by; karmāṇaṁ = actions; tam = him; āhuḥ = they declare; paṇḍitaṁ = the learned; budhāḥ = the wise;॥]
He, whose every undertaking is devoid of desire filled resolutions, whose actions are burnt by the fire of knowledge, him, the learned declare as the wise.
Gīta Bhāshya 4.19
Next five verses (4.19-4.23) describe how actions are burnt by the fire of knowledge.
एतदेव प्रपञ्चयति यस्येत्यादिना श्लोकपञ्चकेन। उक्तप्रकारेण ज्ञानाग्निदग्धकर्माणम् ॥१९॥
etadeva prapañcayati yasyetyādinā ślokapañcakena। uktaprakāreṇa jñānāgnidagdhakarmāṇam ॥19॥
[etadeva = indeed, this (regarding ways of karma); prapañcayati = manifests; yasyetyādinā = starting from 'yasya'; ślokapañcakena = next five verses;। uktaprakāreṇa = in the manner described; jñānāgnidagdhakarmāṇam = actions are burnt by knowledge;]
Indeed, the next five verses, starting from the verse 'yasya', elaborate on how actions are burnt by the fire of knowledge.