Eliot frames Silas's developing Christian morals and his concurrent softening of personality through the metaphor of flowers and buds opening. In Chapter 7, Eliot implies that Silas's environment in Raveloe is nourishing him like rich soil, whether or not he knows it:
This strangely novel situation of opening his trouble to his Raveloe neighbours, of sitting in the warmth of a hearth not his own, and feeling the presence of faces and voices which were his nearest promise of help, had doubtless its influence on Marner, in spite of his passionate preoccupation with his loss. Our consciousness rarely registers the beginning of a growth within us any more than without us: there have been many circulations of the sap before we detect the smallest sign of the bud.
The kindness of Silas's neighbors about his lost gold begins to make a "growth" within him; this is the "growth" of his personality but also refers to the metaphorical "growth" of a tree as it begins to bud. Silas himself is not even aware of this happening yet. The effects of good company are, the author implies, effective but very subtle, like the "many circulations of the sap" that occur before blossoms appear in the Spring.
Many other versions of this metaphor follow, comparing the idea of flowering plants to the unfolding character of the old weaver. By Chapter 15 Silas is blooming so rapidly after adopting Eppie that he sees her as a plant too:
[...] as some man who has a precious plant to which he would give a nurturing home in a new soil, thinks of the rain, and the sunshine, and all influences, in relation to his nursling, and asks industriously for all knowledge that will help him to satisfy the wants of the searching roots, or to guard leaf and bud from invading harm.
Silas wishes to guard Eppie like a precious plant, gather her to his hearth, and provide her with the most nourishing of "soils" in which to grow. He thinks about her progress like a gardener "thinks of the rain, and the sunshine, and all influences." He is willing to reach out to his neighbors and break his isolation as he "industriously" seeks knowledge about parenting Eppie better. Eppie's own development is also compared to the "searching" desires of roots. She might not be Silas's biological daughter, but Eliot shows in this passage that they're metaphorically aligned with each other as "flowering" things.
In Chapter 9, Eliot uses the metaphor of planting the "seed" of an evil or misguided decision to explain why such decisions inevitably hurt the doer. When describing Godfrey's trust in "the throw of Fortune's dice" to solve his relationship problems, she writes:
Let him forsake a decent craft that he may pursue the gentilities of a profession to which nature never called him, and his religion will infallibly be the worship of blessed Chance, which he will believe in as the mighty creator of success. The evil principle deprecated in that religion, is the orderly sequence by which the seed brings forth a crop after its kind.
With this metaphor, Eliot links religious themes of comeuppance and divine revenge to the concept of Godfrey "reaping" what he sows. Many of the important events in Silas Marner reflect the novel's urging to follow Christian teachings. Within the novel's moral universe, then, reliance on luck instead of just acting morally is in itself risky business. Instead of being proactive about his feelings for Nancy and his marriage to Molly, Godfrey chooses to wait and cross his fingers. Because he does not sow a good deed, Eliot implies his actions can only "bring forth a crop" of trouble.
Warnings by the narrator about leaving things to chance recur several times in the novel. The negative consequences of relying on "Chance" always come with commentary from Eliot's narrator about the dangers of straying from the path of moral action. The most obvious example of this is when Silas's fate is changed by the choice to "draw lots" in Lantern Yard. The reader already knows that "Chance" in this novel is not fair, as the unfortunate result of relying on the luck of the draw was the reason the weaver was exiled from his original home in Chapter 1. Trusting any aspect of one's life to luck—instead of good deeds guided by Christian principles—apparently causes characters nothing but misery in Silas Marner.
Silas Marner is as miserly and dry as sand before his real good nature is "unblocked" through his relationship with his adopted daughter. Eliot uses the metaphor of a rivulet (a tiny stream) to describe the flow of goodness working its way through his "soul" in Chapter 10:
The fountains of human love and of faith in a divine love had not yet been unlocked, and his soul was still the shrunken rivulet, with only this difference, that its little groove of sand was blocked up, and it wandered confusedly against dark obstruction.
The flow of emotion in Silas's "soul" is there, Eliot implies, and the horrible events of the weaver's previous existence in Lantern Yard have only "blocked" it. With the right impulse, it can be made to wash open. Silas now only has a trickle of "soul" he can access, but Eliot implies that "fountains" are forthcoming. This is yet more visual imagery that ties Silas's development to the power of growth in the natural world; elsewhere he is described as a flower blooming and as a tree budding.
The essential goodness of Silas's character is emphasized by the smallness of the gesture needed to restore the flow. The "little groove of sand" blocking Silas's progress, a tiny rib of earth that blocks the "rivulet," only needs a tiny push to re-open. It gets a huge one, with Eppie, but that's beside the point. Through this description of a rivulet, the narrator confirms that Silas is a good man underneath all his miserliness. The "water" of his good nature just needs to be given a path.
Eliot frames Silas's developing Christian morals and his concurrent softening of personality through the metaphor of flowers and buds opening. In Chapter 7, Eliot implies that Silas's environment in Raveloe is nourishing him like rich soil, whether or not he knows it:
This strangely novel situation of opening his trouble to his Raveloe neighbours, of sitting in the warmth of a hearth not his own, and feeling the presence of faces and voices which were his nearest promise of help, had doubtless its influence on Marner, in spite of his passionate preoccupation with his loss. Our consciousness rarely registers the beginning of a growth within us any more than without us: there have been many circulations of the sap before we detect the smallest sign of the bud.
The kindness of Silas's neighbors about his lost gold begins to make a "growth" within him; this is the "growth" of his personality but also refers to the metaphorical "growth" of a tree as it begins to bud. Silas himself is not even aware of this happening yet. The effects of good company are, the author implies, effective but very subtle, like the "many circulations of the sap" that occur before blossoms appear in the Spring.
Many other versions of this metaphor follow, comparing the idea of flowering plants to the unfolding character of the old weaver. By Chapter 15 Silas is blooming so rapidly after adopting Eppie that he sees her as a plant too:
[...] as some man who has a precious plant to which he would give a nurturing home in a new soil, thinks of the rain, and the sunshine, and all influences, in relation to his nursling, and asks industriously for all knowledge that will help him to satisfy the wants of the searching roots, or to guard leaf and bud from invading harm.
Silas wishes to guard Eppie like a precious plant, gather her to his hearth, and provide her with the most nourishing of "soils" in which to grow. He thinks about her progress like a gardener "thinks of the rain, and the sunshine, and all influences." He is willing to reach out to his neighbors and break his isolation as he "industriously" seeks knowledge about parenting Eppie better. Eppie's own development is also compared to the "searching" desires of roots. She might not be Silas's biological daughter, but Eliot shows in this passage that they're metaphorically aligned with each other as "flowering" things.
In Chapter 19, when Godfrey Cass and Nancy offer Eppie a home and reveal that Godfrey is her true father, Silas is horrified at the prospect of having another Cass steal his "gold" from him. This time, though, it's because he has become a father in every way that matters to Eppie, and Eliot uses a metaphor to underline how seriously he takes that relationship:
‘Just the same?’ said Marner, more bitterly than ever. ‘How’ll she feel just the same for me as she does now, when we eat o’ the same bit, and drink o’ the same cup, and think o’ the same things from one day’s end to another? Just the same? that’s idle talk. You’d cut us i’ two.’ Godfrey, unqualified by experience to discern the pregnancy of Marner’s simple words, felt rather angry again.
Although Silas could not literally have been "pregnant" with Eppie, his speech to Godfrey reveals that he loves Eppie as though he had birthed her himself. Just as he can't be her mother, he isn't her biological father. However, the reality of the blood relationship is as immaterial to Silas as the distinction between a mother and a father's love. He loves Eppie like a father regardless of Godfrey's biological connection to her. The wordplay of "pregnant" is verbally ironic here, because of the paternal relationship both men have with Eppie. It's also ironic because of what happened to Molly. The last time Godfrey was able to "discern a pregnancy" when Eppie was involved, he did not behave in a fatherly or exemplary way.
Silas doesn't want to take the gold back, when Godfrey offers it just before this exchange, because he doesn't need it. This is partially because the money doesn't matter to him now that he has Eppie, and also because Godfrey doesn't understand what it is he is offering. Giving the gold to Silas and taking Eppie away would essentially be an exchange of one "gold" for another.