Srimad Bhagavatam Canto 02, Chapter 01, Text 19

SB 2.1.19

tatraikavayavam dhyayed
avyucchinnena cetasa
mano nirvisayam yuktva
tatah kiñcana na smaret
padam tat paramam visnor
mano yatra prasidati
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
Thereafter, you should meditate upon the limbs of Visnu, one after another, without being deviated from the conception of the complete body. Thus the mind becomes free from all sense objects. There should be no other thing to be thought upon. Because the Supreme Personality of Godhead, Visnu, is the Ultimate Truth, the mind becomes completely reconciled in Him only.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
Foolish persons, bewildered by the external energy of Visnu, do not know that the ultimate goal of the progressive search after happiness is to get in touch directly with Lord Visnu, the Personality of Godhead. Visnu-tattva is an unlimited expansion of different transcendental forms of the Personality of Godhead, and the supreme or original form of visnu-tattva is Govinda, or Lord Krsna, the supreme cause of all causes. Therefore, thinking of Visnu or meditating upon the transcendental form of Visnu, specifically upon Lord Krsna, is the last word on the subject of meditation. This meditation may be begun from the lotus feet of the Lord. One should not, however, forget or be misled from the complete form of the Lord; thus one should practice thinking of the different parts of His transcendental body, one after another. Here in this verse, it is definitely assured that the Supreme Lord is not impersonal. He is a person, but His body is different from those of conditioned persons like us. Otherwise, meditation beginning from the pranava (omkara) up to the limbs of the personal body of Visnu would not have been recommended by Sukadeva Gosvami for the attainment of complete spiritual perfection. The Visnu forms of worship in great temples of India are not, therefore, arrangements of idol worship, as they are wrongly interpreted to be by a class of men with a poor fund of knowledge; rather, they are different spiritual centers of meditation on the transcendental limbs of the body of Visnu. The worshipable Deity in the temple of Visnu is identical with Lord Visnu by the inconceivable potency of the Lord. Therefore, a neophyte’s concentration or meditation upon the limbs of Visnu in the temple, as contemplated in the revealed scriptures, is an easy opportunity for meditation for persons who are unable to sit down tightly at one place and then concentrate upon pranava (omkara) or the limbs of the body of Visnu, as recommended herein by Sukadeva Gosvami, the great authority. The common man can benefit more by meditating on the form of Visnu in the temple than on the omkara, the spiritual combination of a-u-m as explained before. There is no difference between omkara and the forms of Visnu, but persons unacquainted with the science of Absolute Truth try to create dissension by differentiating between the forms of Visnu and that of omkara. Here it is indicated that the Visnu form is the ultimate goal of meditation, and as such it is better to concentrate upon the forms of Visnu than on impersonal omkara. The latter process is also more difficult than the former.
Srimad Bhagavatam Canto 02, Chapter 01, Text 18
Srimad Bhagavatam Canto 02, Chapter 01, Text 20