Psalms 54:6

6. I will freely sacrifice Hebrew, with a free-will offering I will sacrifice, etc. נדבה , ( nedabah,) is always used for the free-will offering in the Pentateuch, and generally elsewhere. Its peculiarity consisted in its pure spontaneity, springing solely from the willing heart of the worshipper, without the prompting of a legal requirement or an antecedent vow, with which it, namely, the votive offering, stood in contrast. The free-will sacrifices of the text “were not spiritual in opposition to the ritual sacrifices, (as in Psalms 50:14; Psalms 51:17,) but ritual as an outward representation of the spiritual.” Delitzsch. The free-will offering belonged to the class of peace offering on receiving the answer of prayer, and assured acceptance and fellowship with God. The remaining members of the verse corroborate the view here given. It is good That is, thus to give thanks.