B.G 5.06
संन्यासस्तु महाबाहो दुःखमाप्तुमयोगतः। योगयुक्तो मुनिर्ब्रह्म न चिरेणाधिगच्छति ॥६॥
saṁnyāsastu mahābāho duḥkhamāptumaYōgataḥ। Yōgayukto munirbrahma na cireṇādhigacchati ॥6॥
O Arjuna, mere renunciation without being engaged in Yōga results in misery. The monk who is engaged in Yōga attains that Brahman, the supreme reality without delay.
Gīta Tātparya 5.06
Yōga is performing the activities without expectation and offering the results to lord Vishnu. Mere renunciation in the form of abandoning activities results in misery.
"The solution to liberation is Yōga. Its form only is renunciation. That which is offered to lord Vishnu is auspicious and considered as renunciation. There is no other way to renounce."
- states Agni Purana.
Only those activities performed as an offering to lord Vishnu is of the form of Yōga. Without such an attitude, if one renounces just the activities, it only results in misery.
"That which is termed as renunciation, understand it to be Yōga as well." (Gīta 6.2)
- it is stated thus in the future. Because of the speciality of Yōga, compared to mere renunciation, it is separately mentioned.