B.G 2.66 and 67

नास्ति बुदि्धरयुक्तस्य न चायुक्तस्य भावना। न चाभावयतः शान्तिरशान्तस्य कुतः सुखम्॥६६॥

इंद्रियाणां हि चरतां यन्मनोनुविधीयते। तदस्य हरति प्रज्ञां वायुर्नावमिवाम्भसि ॥६७॥

nāsti budidharayuktasya na cāyuktasya bhāvanā। na cābhāvayataḥ śāntiraśāntasya kutaḥ sukham॥66॥

iṁdriyāṇāṁ hi caratāṁ yanmanōnuvidhīyatē। tadasya harati prajñāṁ vāyurnāvamivāmbhasi ॥67॥

[नास्ति बुद्धिः अयुक्तस्य न च युक्तस्य भावना। न च अभावयतः शान्तिः अशान्तस्य कुतः सुखम्॥
nāsti = does not exist; buddhiḥ = wisdom; ayuktasya = without gracefully engaged mind; na = not; ca = and; yuktasya = gracefully engaged; bhāvanā = attitude;। na = not; ca = and; abhāvayataḥ = who is short of; śāntiḥ = peace, liberation; aśāntasya = without peace, or liberation; kutaḥ = how can there be; sukham = happiness;]

[इंद्रियाणां हि चरतां यत् मनः अनुविधीयते। तत् अस्य हरति प्रज्ञां वायुः नावम् इव अम्भसि॥
iṁdriyāṇāṁ = of the senes; hi = certainly; caratāṁ = moves; yat = that; manaḥ = mind; anuvidhīyatē = subservient to; tat = from; asya = it; harati = steals; prajñāṁ = wisdom; vāyuḥ = windy; nāvam = ship is; iva = the way; ambhasi = waters]

For one who is without the gracefully engaged mind, there is no wisdom. Without the graceful attitude, one does not get liberated. Without liberation, where is happiness? Such a mind (without grace) is sub-servient to the movement of senses. Wisdom is stolen from such a mind the way the windy waters carry away a ship.

Gīta Tātparya 2.66 and 67

'shānti' - also means honest endeavour towards the lord.

शान्तिः भगवन्निष्ठा।

śāntiḥ bhagavanniṣṭhā।

[śāntiḥ = 'śāntiḥ' means; bhagavanniṣṭhā = honest endeavour towards the lord;]

'śāntiḥ' means honest endeavour towards the lord.

"शमो मन्निष्ठता।"

इति हि भागवते ॥६४-६६॥

"śamō manniṣṭhatā।"

iti hi bhāgavatē ॥64-66॥

[śamō = 'sha' means; manniṣṭhatā = sincerity of the mind;]

[iti hi = so stated; bhāgavatē = in Bhagavata; ॥64-66॥]

"The root 'sha' means sincerity of the mind"

-so stated in Bhagavata.