I've been contemplating Isaiah 55 and couldn't help but think it offers a great Gospel guideline as we seek to "proclaim the excellencies of Him who called us out of darkness into His marvelous light". (1 Peter 2:9)
Here's my bullet-point thoughts:
vs. 1: "Come, everyone who is thirsty, come to the waters..." The call goes out to all...and the call is to embrace Christ ( Jesus said in John 14:4, "But whoever drinks from the water that I will give him will never get thirsty again--ever! In fact, the water I will give him will become a well of water springing up within him for eternal life."")
vs.1 cont'd: "and you without money; come, buy, and eat! Come, buy wine and milk without money and without cost!" Salvation from our sins, God's judgement, and wrath is a free gift for those who believe, though, it was incredibly costly...it cost Jesus His very life.
vs. 2 "Why do you spend money on what is not food, and your wages on what does not satisfy?" Ecclesiastes calls it "chasing after wind". You'll never have enough and your soul will never find rest until it finds rests in God alone (Augustine). Psalm 107:9 says, "For He has satisfied the thirsty and filled the hungry with good things."
vs. 6 "Seek the Lord while He may be found; call to Him while He is near." Our lives are but a vapor, don't wait, don't presume there may be a tomorrow. 2 Corinthians 6:2b says, "Look, now is the acceptable time; look, now is the day of salvation." Cry out for mercy and grace!
vs. 7 "Let the wicked one abandon his way, and the sinful one his thoughts." Salvation involves not just being saved TO something (eternal life) but it also involves being saved FROM something, our sin. That means, genuine salvation begins with repentance. A broken spirit that sees her sin for what it is, treason against a holy God, and then, disgusted by it, turns away from her sinful ways, thoughts, and actions to Jesus who is "the way, the truth, and the life".
vs.7 cont'd "let him return to the Lord so He may have compassion on him, and to our God for He will freely forgive." 1 John 1:9 says, "If we confess our sins, He is faithful and righteous to forgive us our sins and to cleanse us from all unrighteousness."
vs. 8-9 "For My thoughts are not your thoughts and your ways are not My ways. This is the Lord's declaration. For as heaven is higher than earth, so My ways, and My thoughts than your thoughts." Now what? God saved you but you realize that your thoughts and ways of living have not been what God desires. His ways and thoughts are perfect...true and righteous altogether (Psalm 19:9) He's not left us alone. He's given us His Word to know His thoughts, and, when we are saved, He seals us (places inside of us) His very Spirit, the Holy Spirit, to help us better understand His thoughts and conform us to His ways.
"Thanks be to God for His indescribable gift." I Cor. 9:15