In plain words
The morning pūjā, the midday pūjā, the evening pūjā: these came into being. The sun at daybreak is the form of Brahmā; at midday this sun is the form of Īśvara. At evening this same sun is the form of Viṣṇu. So, at the three sandhyās, it goes on as worship of the Trimūrti. But those who recognise this truth and act on it are rare. We do many karmas unknowingly, so for the atonement of these karmas we must perform these five kinds of yajña every day. For these yajñas we need not set up fire-pits in this way, or altars of any other kind. To bow to the command of mother and father, to think of the gods, whenever the occasion comes to give a little food to the creatures in our home or outside, or to give at least a handful of rice to a beggar, or a little food at least to a few dogs, to think of God and make the effort fit to sustain our birth: this is the very essence of these five yajñas. That is why:
What gift is greater than the gift of food? What God is there beyond mother and father? What conduct of Satya is there beyond japa and tapas? What Dharma is higher than compassion? Look: what gain is greater than the company of the good? What enmity is worse than anger? What disease is worse for men than debt? What death is there on earth worse than ill fame? What wealth is there, at any time, beyond fame? What ornament surpasses smaraṇa?
So human life is most exalted. It is the noblest. Our chief duty is to set this noble human life on the sacred path. To think that we can atone for such sins merely by surface utterances and surface installations of mantras is sheer madness.