Does God speak to us today outside of the Scripture?
There are at least two other verses related to Psalm 19.
One is in Psalm 97: 6 (the other I know of is Psalm 50:6-- I am primarily dealing with Psalm 97:6 because Psalm 50:6 is related in its subject matter.), "The heavens proclaim his righteousness, and all the peoples see his glory." This verse is in the context of God's supreme rule over all. Psalm 97:5 speaks of God being the Lord over all the earth, Psalm 97:9 speaks of the Lord being the most high over all the earth. Seeing what God has created demonstrates as a witness to all humanity that He is supreme (consider that all true science--observational science--proclaims His glorious handiwork) . The sad reality is that most of humanity fails to recognize His kingship due to their sin and suffers the consequences as a result (Philippians 2:5-11).
Psalm 97:6 teaches us that the heavens proclaim specifically the righteousness of the Lord. As I understand it, this verse mainly is a reference to the future (at this point in history in the Psalms and today) when the Lord will return and judge humanity because of their sin (Psalm 50:6; Revelation 16:5; Matthew 24:30; Revelation 1:7; 19: 11-13). I think the fact that the last part of the verse states, "and all the peoples see his glory" gives strong evidence that this verse is speaking about Christ's second coming to earth. Are you ready to meet the Creator and Judge of all humanity (Psalm 50:6)?
At the second coming, the Bible states that every eye will see Christ (Revelation 1:7; Zechariah 12:10).The Scripture teaches us that the first time Christ came to earth as a Lamb (John 1:29) to take away the sins of the world; the Scriptures also teaches us that there is a second coming in the future where the Lord will return as the Lion of the Tribe of Judah (Revelation 5:1-14). Why? The reason is the Lord needs to judge humanity's sin (Psalm 50:6; 2 Peter 3:7,10), and fulfill all His promises (like the land promises for Israel) He has made to Abraham, King David, to the people of Israel, and to the church. Christ is coming, the heavens declare His righteousness, and all will see His glory as He judges justly. Again, are you ready?
The fact that from Scripture we learn that the heavens speak today offers hope to all humanity that they too can know personally God's glory as Savior (2 Peter 3:7-10). God does not take delight in judging the sinner (Ezekiel 18:23; 32); rather, God prefers that the sinner turns from his sin to realize salvation in Him. Have you done that? Have you turned to Christ and been rescued from the wages of your sin? If not, do so now before the Lord returns or before you die. Remember, once your life ends it is too late to be saved (Romans 6:23).
