Shatapatha Brahmana 10.3.5.9

10.3.5.9

ya u haivaṃvidaṃ sveṣu pratipratirbubhūṣati na haivālam bhāryebhyo bhavatyatha ya evaitamanubhavati yo vai tamanu bhāryānbubhūrṣati sa haivālam bhāryebhyo bhavati

And if any one strives to become a rival among his own people to one who knows this, he does not satisfy his dependants; but, indeed, only he satisfies his dependants, who is faithful to that one and who, along with him, strives to support his dependants.