John Wesley on Numbers 6:14

A sin - offering - Whereby he confessed his miscarriages, notwithstanding the strictness of his vow and all the diligence which he could use, and consequently acknowledged his need of the grace of God in Christ Jesus the true Nazarite. For peace - offerings - For thankfulness to God, who had given him grace to make and in some measure to keep such a vow. So he offered all the three sorts of offerings, that he might so far fulfil all righteousness and profess his obligation to observe the will of God in all things.