Numbers 18:11-14 King James Version (KJV)
11 And this is thine; the heave offering of their gift, with all the wave offerings of the children of Israel: I have given them unto thee, and to thy sons and to thy daughters with thee, by a statute for ever: every one that is clean in thy house shall eat of it.
12 All the best of the oil, and all the best of the wine, and of the wheat, the firstfruits of them which they shall offer unto the LORD, them have I given thee.
13 And whatsoever is first ripe in the land, which they shall bring unto the LORD, shall be thine; every one that is clean in thine house shall eat of it.
14 Every thing devoted in Israel shall be thine.

Numbers 18:11-14 Amplified Bible (AMP)

11 And this also is yours: the heave offering of their gift, with all the wave offerings of the Israelites. I have given them to you and to your sons and to your daughters with you as a continual allowance forever; everyone in your house who is [ceremonially] clean may eat of it.
12 All the best of the oil, and all the best of the [fresh] wine and of the grain, the firstfruits of what they give to the Lord, to you have I given them.
13 Whatever is first ripe in the land, which they bring to the Lord, shall be yours. Everyone who is [ceremonially] clean in your house may eat of it.
14 Every devoted thing in Israel [everything that has been vowed to the Lord] shall be yours.

Amplified Bible (AMP) Copyright © 1954, 1958, 1962, 1964, 1965, 1987 by The Lockman Foundation

These are my thoughts, please share yours.

11 We as Christians are made clean by the blood of Christ, the priests were made clean by the blood of the lamb but this cleanliness was only for a short time the blood of Christ lasts, we as Christians receive blessings from Christ because of our service to Him.

12 When we come to Christ He has nothing but the best for us. We are to also give our best and all to the Lord. We are not to keep anything from Him, what He has for us is better than what we could plan for ourselves.

13 Our blessings from God and chances to serve Him will only come if we are clean if things are right between us and the Lord. We will not be able to take part in service to Him effectively if we are clean, if we have unresolved sins in our lives.

14 We are to give everything to the Lord because He gives everything we could ever need, the best of which was Him dying for us on the cross to give us hope.