Masakikute imo ga iwawaba okitsu nami chie ni tatsu tomo sawari arame ya mo

ま幸くて妹が斎はば沖つ波
千重に立つとも障りあらめやも

Roma-ji: Masakikute imo ga iwawaba okitsu nami chie ni tatsu tomo sawari arame ya mo
English Translation: If you stay safe and well
and keep yourself pure in prayer,
though the offshore waves
rise up a thousandfold
could any harm befall me
Meaning: If you stay well and keep yourself pure in prayer for me, then though the waves of the open sea rise a thousandfold, what harm could come to me?
Commentary: Book Fifteen Poems of the Envoys to Silla 3583

Headnote continued from the preceding poem: "The envoys sent to Silla grieve at parting and exchange poems, express their sorrowful feelings on the sea route, and recite old poems suited to the places they pass"
The husband answers his wife's wish in the preceding poem, encouraging her: if she stays well and prays for him, he need not fear the rough waves. It was believed that a traveler's safety was guarded by the "iwai" of those at home, who kept themselves pure and prayed to the gods. By relying on her prayers, he seeks to ease her anxiety.
The first half of this book gathers the poems of the embassy sent to Silla in the eighth year of Tenpyō (736), arranged in the order of the journey from the departure at Naniwa to the return. A left note reads "the above eleven poems are an exchange," and these opening eleven poems are the parting exchanges between the envoys and their wives before departure. None of the authors is named.

First line, "masakikute": "ma" is a prefix; being safe and well. It presupposes his wife's safety.
Second line, "imo ga iwawaba": "iwau" means to purify oneself, worship the gods, and pray for safety.
Third line, "okitsu nami": "tsu" is an old attributive particle: the waves of the open sea.
Fourth line, "chie ni tatsu tomo": "chie" means many layers; "tomo" is a concessive conditional: even though they rise.
Fifth line, "sawari arame ya mo": "ya mo" is rhetorical, firmly denying: could there be any hindrance? Surely not. The word answers "tsutsumu koto naku" in the preceding poem, 3582.
Source: Manyoshu
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