Lynn – It is time to cast all of your care onto the Lord. He will carry it for you. You do not have to carry it any longer. After you cast the care onto the Lord, do not pick it up again. Our ancient enemy will try to put the burden back on you. Don’t receive it. Just say: “No. I do not receive the burden of my husband’s salvation. God is taking care of that. It is not my concern anymore.”
  You said that Mark has heard the gospel. That he knows the plan of salvation. That you have given him the word and all the information is necessary for him to be saved.
  Here are some scriptures to read, meditate, ponder and believe and trust in:
  The first is Isaiah 55.11 – God’s word will not return unto Him void. It will accomplish what God pleases. It will prosper in the thing whereunto He has sent it.
  Next look at second Peter 3.9 – The Lord is not slack concerning His promise…He is longsuffering to us-ward, not willing that any should perish, but that all should come to repentance.  Stated another way He is saying it is His will all be saved. Will they be? Of course not. But you have locked on to Mark. You have claimed him for the kingdom of God. Have faith in your prayers, as they are the will of God.
  Fear, worry and inordinate concern is actually faith that God’s promise will fail. Don’t get caught in that trap. It will rob you of the very thing you most desire.
  This is key: First John 5.14-15 --  “And this is the confidence we have in Him, that if we ask anything according to His will, He hears us; and if we know that He hears us – whatsoever we ask – we know we have the petition that we desired of Him.”
  You may never see the evidence of Mark’s salvation. Trust God’s word. Have faith in your prayers. Believe God to do the work in Mark’s heart
That you have started by sowing the seed of the word into him.
  Here is an example of what I mean. I have a friend who is as a rodeo cowboy and an evangelist.  He knew a young bareback bronc rider on the rodeo circuit. He spoke to the boy (18 years old) about his salvation and went through the scriptural steps necessary.
  The boy said he really appreciated the information, but he just wasn’t ready to take that step. He was young, he had a lot living to do, he was having good success rodeoing. He would think it over, and maybe someday…”
  Two months later up in Wyoming the boy was bucked off a horse.  His head hit the ground and he was instantly killed.
  Later that year my friend was passing through the small Oklahoma town where the boy’s family lived.
He figured the mother would still be mourning her son and that he could offer some comfort.
  Instead of mourning he found the mother going about her household tasks cheerfully. She said that when she heard her son was killed she was devastated. She went to the Lord in prayer and reminded God of His promise that He would not give her more than she could bare. She told God that this burden was indeed more than she could bare.
  She said while she was still in prayer the Holy Spirit spoke to her in a strong, unmistakable voice:
“From the saddle to the ground, I was sought, and I was found.”