Let thy mercies come also unto me, O Lord - This commences a new portion of the psalm, in which each verse begins with the letter Vau (ו v, or “v”). There are almost no words in Hebrew that begin with this letter, which is properly a conjunction, and hence, in each of the verses in this section of the psalm Psalms 119:41-48 the beginning of the verse is in the original a conjunction - .ו This does not here indicate a connection, as with us the conjunction “and” would naturally do; but is a mere artificial arrangement in order that the verse may begin with that letter, and it in no manner affects the sense. The phrase “Let thy mercies come” is literally, “and thy mercies shall come,” or “and let thy mercies come.” That is, Let thy mercy be manifested to me; let me experience thy mercy and thy favor.
Even thy salvation - mercy connected with salvation, or that leads to salvation.
According to thy word - According to the promises of thy word; according to the arrangements which thou hast made, and hast revealed. The only hope of mercy is that which is held out in the word of God.