We are in third section of chapter 05, first section talked about how Karma Yoga brings same result but is easier than Jyana Yoga. And the remaining Chapter describes how Karma Yogis stays free from bondage. So 07 to 16 describes how fixing mind on Atma keeps a Karma Yogi free from Bondage. 17 to 29 talks about how fixing mind on Parmatama frees Karma Yogis from bondage.

So we discussed in 17th verse how four faculty in our subtle setup …

tad-buddhayas tad-ātmānas
tan-niṣṭhās tat-parāyaṇāḥ
 the intelligence, the mind, the faith and the goal we center them on Sri Krishna and those who do that develops an equal vision towards all living beings, now Sri Krishna will describe what will be the result of those equal vision, those who have the equal vision are as good as liberated even being in this material world. So 05.19 

Bg 5.19

ihaiva tair jitaḥ sargo
yeṣāṁ sāmye sthitaṁ manaḥ
nirdoṣaṁ hi samaṁ brahma
tasmād brahmaṇi te sthitāḥ

Word for word: 

iha — in this life; eva — certainly; taiḥ — by them; jitaḥ — conquered; sargaḥ — birth and death; yeṣām — whose; sāmye — in equanimity; sthitam — situated; manaḥ — mind; nirdoṣam — flawless; hi — certainly; samam — in equanimity; brahma — like the Supreme; tasmāt — therefore; brahmaṇi — in the Supreme; te — they; sthitāḥ — are situated.

Translation: 

Those whose minds are established in sameness and equanimity have already conquered the conditions of birth and death. They are flawless like Brahman, and thus they are already situated in Brahman.

 

ihaiva  -> iha + eva. iha — in this world, in this life itself. Eva -> Certainly. taiḥ — by them; jitaḥ sargo -> They have conquered over, Sargah is cycle of birth  and death. Who are they? yeṣāṁ sāmye sthitaṁ manaḥ -> Those whose mind is situated in Samya – equanimity, so Samya is related with the word Samdarshina from previous verse 05.18d, this is repeated here twice 5.19 b & c. samya is equanimity and then what is the nature of the equanimity that makes them as good as Brahm nirdoṣaṁ, there is no dosha, no faults, they are gone beyond the three modes  nirdoṣaṁ  hi samaṁ brahma, so what is beyond the three mode is Brahm so they have become as good as Brahm therefore tasmād brahmaṇi te sthitāḥ, therefore they are situated in Brahm, so here Sri Krishna describes how an equal vision can situate a person in Brahm, so actually speaking the soul is transcendental and for the soul what is happening in the material realm doesn’t matter because everything in the material realm is temporary, it just comes and it goes it doesn’t matter for the soul, now why it matters is because the soul is attached, the soul thinks that this will make me happy that will make me miserable, but the soul there is samah nothing material can make soul happy because I am not material I am transcendental, my real life is a life of spirit not life of matter. So naturally when a person sees everything material equally then naturally there is no more attachment to matter and to the excitement about what changes happen in world of matter, and that itself is liberation. What is bondage? Bondage is caused by our own desires to enjoy this world and the desire to enjoy this world is present because we think that there are certain things in this world is enjoyable and certain things are one on which someone lament we wanted to avoid them but when we don’t feel like this when we are sama then that is as good as liberation from bondage. 

So Srila Prabhupada explains what flawless means? Nirdosham, The Lord is flawless because He is without attraction or hatred. So Raga and Dvesha that is based on illusion and that creates flaws within us, so similarly when a living entity is without attraction or hatred, he also becomes flawless and eligible to enter into spiritual sky. To enter into spiritual sky that means Srila Prabhupada uses the word Brahman to mean the Lord over here.

Brahman can mean Brahma Jyoti it can mean Bhagvan, as the Bhagavad Gita Thought will evolve we will see that Arjuna will tell Sri Krishna is Param Brahma, he is Brahma in the highest manifestation, So what Srila Prabhupad is giving us here that Sri Krishna will confirm later in Bhagavad Gita, so flawlessness means one is not having attachment or aversion, now the question will come does one become situated in this Brahman platform. So Sri Krishna said tad-buddhayas tad-ātmānas
tan-niṣṭhās tat-parāyaṇāḥ