According to some forms of dispensationalism, in the church age alone is salvation offered freely, obtained through faith in the gospel of the grace of God, but according to other views, salvation has always been offered freely, acquired through faith in Jesus Christ: in the former ages by faith in the coming Mesiah, in the present age by faith in the Christ that came.
What is your opinion?
Neither one is strictly true.
Salvation is not obtained ( actively ) through faith in the Gospel, but is "obtained" from the hand of God because eternal life is a gift ( Romans 6:23 )...
Bestowed upon whom He will have mercy and grace towards ( Romans 9:16 ).
The Lord Jesus has been given a group of people, His "sheep", to save;
Only those that were given to him by God the Father, will be saved ( John 17:2 ).
Belief of the Gospel is one evidence ( of many ) that God has called someone to Himself, through His power and through His kindness towards them.
The Gospel of Jesus Christ is not an offer, it's a promise made to only those who believe, from the heart ( Romans 10:8-20 ).
Those who call upon ( and have called upon ) the Lord out of a pure heart ( 2 Timothy 2:22 ) and in truth ( Psalms 145:18 ) in
all generations, were
made new creatures by the merciful hand of the Lord...
They were chosen by Him to be part of a godly remnant ( a people sanctified unto Himself and made holy by the blood of His Son ) out of all mankind, and
caused to approach through the operation of His Spirit through the new birth ( Psalms 65:4, John 6:37-65, Romans 8:1-30, Romans 9:6-24, Ephesians 1:1-14, Ephesians 2:1-10, 2 Thessalonians 2:13-14 ) and through the word of God Himself ( James 1:18 ).
See Hebrews 11 for some of the names of those who were given the gift ( Ephesians 2:8, Philippians 1:29, Hebrews 12:2 ) of genuine faith, my friend....
A faith that trusts and believes in God to the saving of the soul ( Hebrews 10:38-39 ), and a faith in Him that survives even severe trials and tribulations that test them in this life.