The blessings and curses (ch. 26) were in a sense God's vows to His people. This chapter deals with His people's vows to Him. Another connection between these chapters is that in times of divine discipline (26:14-33) people tend to make vows to God. Chapter 27 shows how God wanted the Israelites to honor their vows.303
"The directions concerning vows follow the express termination of the Sinaitic lawgiving (chap. xxvi. 46), as an appendix to it, because vows formed no integral part of the covenant laws, but were a freewill expression of piety common to almost all nations, and belonged to the modes of worship current in all religions, which were not demanded and might be omitted altogether, and which really lay outside the law, though it was necessary to bring them into harmony with the demands of the law upon Israel."304
"Just as the whole of the giving of the Law at Sinai began with ten commandments, so it now ends with a list of ten laws. The content of the ten laws deals with the process of payment of vows and tithes made to the Lord."305
God did not command the Israelites to make vows or to promise anything to Him. However vowing is a natural desire of people who love God or want things from God. Therefore God gave the Israelites regulations that were to govern their vowing and dedicating. Though God did not command vows He expected that once His people made them they would keep them (cf. Prov. 20:25; Eccles. 5:3-5). It may be that part of the purpose of these regulations was to discourage rash swearing by fixing a relatively high price on the discharge and changing of vows.306
"A vow to God placed a person or property in a special consecrated relationship which stood outside the formal demands of the law."307
Old Testament examples of people who made vows are Jephthah (Judg. 11:30-31) and Hannah (1 Sam. 1:11). Votive offerings were offerings made in payment of vows.
A vow was a promise to give oneself or one's possessions to God so He would bestow some blessing or because He had already bestowed a blessing. People made vows to do something or not to do something. Vows were normally temporary. When a person wanted to get back what he had vowed to God he had to pay a certain price to the sanctuary to buy back what he had given to God. This constituted redeeming what the person had vowed.