dravya-yajñās tapo-yajñā
yoga-yajñās tathāpare
svādhyāya-jñāna-yajñāś ca
yatayaḥ saḿśita-vratāḥ

Translation of Bhagavad Gita 4.28

Having accepted strict vows, some become enlightened by sacrificing their possessions, and others by performing severe austerities, by practicing the yoga of eightfold mysticism, or by studying the Vedas to advance in transcendental knowledge.

Commentary by Sri A.C. Bhaktivedanta Swami Prabhupada of Gaudiya Sampradaya:

These sacrifices may be fitted into various divisions. There are persons who are sacrificing their possessions in the form of various kinds of charities. In India, the rich mercantile community or princely orders open various kinds of charitable institutions like dharma-sala, anna-kshetra, atithi-sala, anathalaya and vidya-pitha. In other countries, too, there are many hospitals, old age homes and similar charitable foundations meant for distributing food, education and medical treatment free to the poor. All these charitable activities are called dravyamaya-yajna. There are others who, for higher elevation in life or for promotion to higher planets within the universe, voluntarily accept many kinds of austerities such as candrayana and caturmasya. These processes entail severe vows for conducting life under certain rigid rules. For example, under the caturmasya vow the candidate does not shave for four months during the year (July to October), he does not eat certain foods, does not eat twice in a day or does not leave home. Such sacrifice of the comforts of life is called tapomaya-yajna. There are still others who engage themselves in different kinds of mystic yogas like the Patanjali system (for merging into the existence of the Absolute), or hatha-yoga or ashtanga-yoga (for particular perfections). And some travel to all the sanctified places of pilgrimage. All these practices are called yoga-yajna, sacrifice for a certain type of perfection in the material world. There are others who engage themselves in the studies of different Vedic literatures, specifically the Upanishads and Vedanta-sutras, or the Sankhya philosophy. All of these are called svadhyaya-yajna. or engagement in the sacrifice of studies. All these yogis are faithfully engaged in different types of sacrifice and are seeking a higher status of life. Krishna consciousness, however, is different from these because it is the direct service of the Supreme Lord. Krishna consciousness cannot be attained by any one of the above-mentioned types of sacrifice but can be attained only by the mercy of the Lord and His bona fide devotees. Therefore, Krishna consciousness is transcendental.

Commentary by Sri Vishvanatha Chakravarthi Thakur of Gaudiya Sampradaya:

Those who offer goods in charity (dravya yajna), those who perform austerities like candrayana vrata (tapo yajna), those who engage in astanga yoga (yoga yajna), those who put effort into engaging in knowledge by studying the Vedas—all these engage in very severe (samsita) vrata.

Commentary by Sri Ramanuja of Sri Sampradaya:

4.28 Some Karma Yogins perform the sacrifice of material objects. Some worship the gods with materials honestly acquired. Some practise charity, some engage themselves in sacrifices and in making oblations into the sacred fire. All these perform sacrifice with material objects. Some do the sacrifice of austerity by devoting themselves to Krcchra, Candrayana, fast, etc. Others perform the sacrifice of Yoga. Some devote themselves to making pilgrimages to sacred sanctuaries and holy places. Here the term Yoga means pilgrimages to sacred sancturaries and holy places as the context relates to aspects of Karma Yoga. Some are devoted to recitation of Vedic texts and some to learning their meaning. They are all devoted to the practice of self-control and of strict vows, i.e., they are men to steady resolution.

Commentary by Sri Sridhara Swami of Rudra Sampradaya:

There are others who unable to perform austerities themselves give charity and feed all the guests at the festivals of the Supreme Lord and also give donations to the twice born Vaisnavas and Brahmins to perform yagnas or offerings of worship to propitiate the Supreme Lord. These practitioners are known as arthayagnas. Yoga is the science of the individual consciousness in communion with the ultimate consciousness. In this state the modifications of the mind are totally controlled. Those who practice this are called yogayagnas. Others practice intense study of the Vedic scriptures by analysing the purport and contemplating its meaning. Then there are those who persevere of unbreakable vows who are never deterred.

Commentary by Sri Madhvacharya of Brahma Sampradaya:

Those who donate artha or wealth for Vedic festivals and rituals also perform yagnas or offerings of worship. Those who perform tapasya or austerities as penance such as fasting for the propitiation of the Supreme Lord also are considered to be offering oblations in yagna. When such austere penance’s are offered as propitiation to the Brahman or the spiritual substratum pervading all existence, the penance itself becomes the sacrificial fire. Such an offering is spiritualised by the Brahman and is an offering in wisdom. Offering in wisdom is to attain the realisation that all knowledge and all propensities is ultimately for the realisation of the atma or soul which gives direct communion to the Supreme Lord Krishna. There is a more profound meaning to the word dravya which normally means donations and that is in reference to the nine dravya’s that compose the physical body being earth, fire, water, air, ether, the senses, the mind, the intellect and the soul. Offering one’s everything is also considered offering all one’s possessions and superior to mere wealth. The great sage Yagnavalkya has echoed this by his statement in the Brihadaranya Upanisad II.II.V that there is no hope for moksa or liberation through wealth.

Commentary by Sri Keshava Kashmiri of Kumara Sampradaya:

Here Lord Krishna reveals others who earn money honestly and donate funds to qualified Vaisnavas and Brahmins to perform yagna or offering of worship to propitiate the Supreme Lord. They also offer foodstuffs to feed all the guests at the Supreme Lord’s festivals. They bear the expense of building temples to the Supreme Lord Krishna or His authorised incarnations as well. This is known as arthayagna. Some perform austerities such as special fasting during the time which corresponds from amavasya or the new moon to purnima or the full moon and back again to amavasya. Others perform yagna by practicing the eight-fold yoga system such as yama or forbearance, niyama or restraint, asanas or postures, pranayama or breathing exercises, pratyahara or withdrawal, dharana or focused attention and samadhi or complete absorption in meditation. Others strive by observing austere vows, others perform yagna by intense study of the Vedic scriptures.

Commentary by Sri Adi Shankaracharya of Advaita Sampradaya:

4.28 Tatha, similarly; apare, others; are dravya-yajnah, perfomers of sacrifices through wealth-those sacrificers who spend wealth (dravya) in holy places under the idea of performing sacrifices; tapo-yajnah, performers of sacrifices through austerity, men of austerity, to whom austerity is a sacrifice; [This is according to Ast.-Tr.] yogayajnah, performers of sacrifice through yoga-those to whom the yoga consisting in the control of the vital forces, withdrawal of the organs, etc., is a sacrifice; and svadhyaya-jnana-yajnah, performers of sacrifices through study and knowledge. Sacrificers through study are those to whom the study of Rg-veda etc. accroding to rules is a sacrifice. And sacrificers through knowledge are those to whom proper understanding of the meaing of the scriptures is a sacrifice. Others are yatayah, ascetics, who are deligent; samsita-vratah, in following severe vows. Those whose vows (vratah) have been fully sharpened (samsita), made very rigid, are samsita-vratah. [Six kinds of sacrifices have been enumerated in this verse.] Further,

Commentary by Sri Abhinavagupta of Kaula Tantra Sampradaya:

4.27-28 Sarvani etc. Dravyayajnak etc. Again all the activities of their sense-organs, the activities of their mind, and the activities of their vital airs, such as issuing through the mouth and nose, driving down the urine etc., other [seekers] established in the fire of concentration, named Yoga, which is the means for subduing the self i.e., the mind, and which is set ablaze by i.e., to be filled with, knowledge. The idea is this : With their intellect that has completely abandoned all other activities due to their concentration on the object, they receive the object that is being perceived on conceived. That has been stated in the Sivopanisad : ‘When the intellect, concentrated on a certain object, not rejected, would not go to another object, at that time the meditation, remaining in the core of the objects, blossoms very much.’ Thus the Yoga-sacrifices are explained. So far the performers of the material-object-sacrifices, the austerity-sacrifices, and the yoga-sacrifices have been defined. Those, who are the performers of the svadhyaya-knowledge-sacrifices are defined now [as] –

Sanskrit Shloka Without Transliteration Marks:

dravya-yajñas tapo-yajña
yoga-yajñas tathapare
svadhyaya-jñana-yajñas ca
yatayah samsita-vratah

Sanskrit to English Word for Word Meanings:

dravya-yajñāḥ — sacrificing one’s possessions; tapaḥ-yajñāḥ — sacrifice in austerities; yoga-yajñāḥ — sacrifice in eightfold mysticism; tathā — thus; apare — others; svādhyāya — sacrifice in the study of the Vedas; jñāna-yajñāḥ — sacrifice in advancement of transcendental knowledge; ca — also; yatayaḥ — enlightened persons; saḿśita-vratāḥ — taken to strict vows.