To meditate upon the lotus feet of the Lord means
SB Canto 1
Thus the King, the worthy descendant of the Pāṇḍavas, decided once and for all and sat on the Ganges' bank to fast until death and give himself up to the lotus feet of Lord Kṛṣṇa, who alone is able to award liberation. So, freeing himself from all kinds of associations and attachments, he accepted the vows of a sage.
The water of the Ganges sanctifies all the three worlds, including the gods and the demigods, because it emanates from the lotus feet of the Personality of Godhead Viṣṇu. Lord Kṛṣṇa is the fountainhead of the principle of viṣṇu-tattva, and therefore shelter of His lotus feet can deliver one from all sins, including an offense committed by a king unto a brāhmaṇa. Mahārāja Parīkṣit, therefore, decided to meditate upon the lotus feet of Lord Śrī Kṛṣṇa, who is Mukunda, or the giver of liberations of all description. The banks of the Ganges or the Yamunā give one a chance to remember the Lord continuously. Mahārāja Parīkṣit freed himself from all sorts of material association and meditated upon the lotus feet of Lord Kṛṣṇa, and that is the way of liberation. To be free from all material association means to cease completely from committing any further sins. To meditate upon the lotus feet of the Lord means to become free from the effects of all previous sins. The conditions of the material world are so made that one has to commit sins willingly or unwillingly, and the best example is Mahārāja Parīkṣit himself, who was a recognized sinless, pious king. But he also became a victim of an offense, even though he was ever unwilling to commit such a mistake. He was cursed also, but because he was a great devotee of the Lord, even such reverses of life became favorable. The principle is that one should not willingly commit any sin in his life and should constantly remember the lotus feet of the Lord without deviation. Only in such a mood will the Lord help the devotee make regular progress toward the path of liberation and thus attain the lotus feet of the Lord. Even if there are accidental sins committed by the devotee, the Lord saves the surrendered soul from all sins, as confirmed in all scriptures.