"I saw that all heaven is interested in our salvation; and shall we be indifferent? Shall we be careless, as though it were a small matter whether we are saved or lost? Shall we slight the sacrifice that has been made for us? Some have done this. They have trifled with offered mercy, and the frown of God is upon them. God's Spirit will not always be grieved. It will depart if grieved a little longer. After all has been done that God could do to save men, if they show by their lives that they slight Jesus’ offered mercy, death will be their portion, and it will be dearly purchased. It will be a dreadful death; for they will have to feel the agony that Christ felt upon the cross to purchase for them the redemption which they have refused. And they will then realize what they have lost—eternal life and the immortal inheritance. The great sacrifice that has been made to save souls shows us their worth. When the precious soul is once lost, it is lost forever. 1T 124.1"
"How shall we escape, if we neglect so great salvation; which at the first began to be spoken by the Lord, and was confirmed unto us by them that heard him;"
Both passages address the danger of neglecting salvation and the consequences thereof. EGW expands on the idea of neglecting salvation, making the connection more explicit.
"And grieve not the holy Spirit of God, whereby ye are sealed unto the day of redemption."
Both passages warn against grieving the Holy Spirit. EGW's statement that 'God's Spirit will not always be grieved' directly echoes the sentiment in Ephesians 4:30.
I have seen an angel standing with scales in his hands weighing the thoughts and interest of the people of God, especially the young. In one scale were the thoughts and interest tending heavenward; in the other were the thoughts and interest tending to earth. And in this scale were thrown all the reading of storybooks, thoughts of dress and show, vanity, pride, etc. Oh, what a solemn moment! the angels of God standing with scales, weighing the thoughts of His professed children—those who claim to be dead to the world and alive to God. The scale filled with thoughts of earth, vanity, and pride quickly went down, notwithstanding weight after weight rolled from the scale. The one with the thoughts and interest tending to heaven went quickly up as the other went down, and oh, how light it was! I can relate this as I saw it; but never can I give the solemn and vivid impression stamped upon my mind, as I saw the angel with the scales weighing the thoughts and interest of the people of God. S…
"TEKEL; Thou art weighed in the balances, and art found wanting."
The EGW passage directly uses the imagery of scales to weigh the thoughts and interests of people, mirroring the Daniel verse where Belshazzar is weighed in the balances and found wanting. The connection is strong and specific.