A woman is permitted to nurse while she is saying Tehillim. However, a man should not say Tehillim in front of her if her breasts are uncovered.
Sources and Explanations
Regarding whether a man may read or say devarim shebikdushah (matters of holiness) in front of a nursing woman whose breasts are uncovered, the Ben Ish Chai (Parashat Bo, ot 10) cites both stringent and lenient opinions. He writes: “A woman who is nursing her child and uncovers her breasts, it is forbidden to read or recite a berachah in front of her, even if she is his wife, and all the more so another woman. Some say that since a woman’s practice is to uncover her breasts at the time of nursing, the breasts are considered at that time like the palms of the hands and the face, and only when she is not nursing, when her practice is to keep her breasts concealed and she is particular about this, is it forbidden to read in front of her. One may rely on this reasoning in a pressing situation.”
However, Rabbi Ovadia Yosef zt”l in Halichot Olam (vol. 1, p. 122) writes emphatically that it is forbidden to read in front of her when her breasts are uncovered, even in a pressing situation; only if he closes his eyes or turns his face to another direction may he read and recite a berachah in front of her.
All the above, however, applies to a man reading in front of the woman, but the woman herself is permitted to read in this state. It goes without saying that if she covers herself in the manner of women there is no prohibition at all; on the contrary, it is a mitzvah to engage in saying Tehillim and not to occupy oneself with idle matters. But even where she is in a private place with no one present and she does not cover herself, there is still no prohibition, for the Shulchan Aruch (Orach Chaim 206:3) permits a woman to read while unclothed, provided that her ervah (private area) is covered. He writes: “One should not recite a berachah unclothed until he covers his ervah. When does this apply? To a man, but a woman may sit with her lower face pressed against the ground, for in this way her ervah is covered.” So too in the Rama (74:4): “If they are unclothed, their ervah must be pressed against the ground, or they must sit on some other object, for then their heart does not see their ervah, which is not the case with a man.” And the Rama reiterated this a second time (75:1): “A woman by herself may read even though she is unclothed.” The Ishei Yisrael (chapter 55, halacha 14) likewise cites this as halachah: “A woman herself may read and recite a berachah when she is not dressed, provided that she covers her ervah.”
And although this is indeed permitted for a woman, it is proper for her to cover her body while she is engaged in matters of holiness and saying Tehillim. See Mishnah Berurah (74:22).
From the sefer “Shaf Veyativ – Laws of Saying Tehillim” by Rabbi Shay Tahan, Chapter 7: What Is Forbidden and Permitted When Saying Tehillim, Halacha 2 (p. 122 in the print edition). Translated from the Hebrew original.
