Advice on Sati in Rig Veda
Let those unwidowed dames with noble husbands adorn themselves with
fragrant balm and unguent. Decked with fair jewels, tearless, free
from sorrow, first let the dames go up to where he lieth.
Rise, come unto the world of life, O woman; come, he is lifeless by
whose side thou liest. Wifehood with this thy husband was thy portion,
who took thy hand and wooed thee as a lover.
Rig Veda X.18.7–8
I am adding some extra material on this subject. Medhatithi, the 9th century polymath, does not mention the Rig Veda when he criticizes Sati in his commentary on Manu Smriti. He shows that Sati violates the Vedas.
कामं तु क्षपयेद् देहं पुष्पमूलफलैः शुभैः । न तु नामापि गृह्णीयात्
पत्यौ प्रेते परस्य तु ॥ १५५ ॥
kāmaṃ tu kṣapayed dehaṃ puṣpamūlaphalaiḥ śubhaiḥ | na tu nāmāpi
gṛhṇīyāt patyau prete parasya tu || 155 ||
Well might she macerate her body by means of pure flowers, roots and
fruits; but she should not even mention the name of another man, after
her husband is dead—(155).
Manu Smriti 5.155
Medhātithi’s commentary (manubhāṣya):
What has been said in the preceding verse is explained more
specifically in the present verse.
As in the case of men, so in that of women also suicide is forbidden.
As for what Aṅgiras has said—‘they should die after their
husband’,—this also is not an obligatory act, and so it is not that it
must be done. Because in connection with it there is an eulogium
bestowed upon the results proceeding from such suicide. Thus then, the
performing of the act being possible only for one who is desirous of
obtaining the said result, the act stands on the same footing as the
Śyena sacrifice. That is, in connection with the Śyena sacrifice we
have the Vedic text—‘one may kill living beings by means of the Śyena
sacrifice,’—and this makes the performance of this sacrifice possible;
but only for one who has become blinded by extreme hatred; so that
when the man does perform the act, it does not become regarded as
‘Dharma,’ a ‘meritorious act’; exactly in the same manner, when the
widow happens to have a very strong desire for the results accruing
from the act of suicide, it is open to her to disobey the prohibition
of it and kill herself; but in so doing she cannot be regarded as
acting according to the scriptures. From this it is clear that the act
of killing herself after her husband is clearly forbidden for the
woman. Further, in view of the distinct Vedic text—‘one shall not die
before the span of his life is run out’—being contradicted by the
Smṛti-text of Aṅgiras, this latter is open to bring assumed to have
some other meaning. Just as in the case of the Smṛti rule ‘one should
take the final bath after having read the Veda’,—the injunction of the
bath, as pertaining to one who has not yet studied the meaning of the
Vedic texts, has been taken as having a different meaning.
Commentary of Medhatithi of Manu Smriti 5.155